Fair enough but has it been any easier for gay men over the years? Certainly as a group gay men have experienced their fair share of ostracism but as a group they seem a lot more jovial anyway.
I am not trying to start a, “it’s harder being a gay man/woman” debate. Just saying they have both had their share of societal challenges but the responses to those challenges seems distinctly different.
I recommend a trip to St. Louis, MO to the bar Novak’s. It’s a lesbian/gay bar. I am neither but I have gay friends and it’s a really great bar. Most of the people there are not straight. Most of the lesbians there are crazy outgoing, loud, laughing, dancing, drinking, social, etc. I have a few lesbian friends that are all perma-stoned hippie types. Not serious at all. I actually know no serious or dour lesbians. Maybe I hang out with too young a crowd? A lot of the lesbians at Novak’s are more “butch” - wear polos, longer shorts, baseball caps, bandannas, sneakers, short hair, etc but a lot of them are young. There are also the older flannel clad ones. Few are ones you wouldn’t guess were lesbian, no stereotypical outward signs - my friend Patrick was hitting on a girl and then her gf came over and got jealous. Maybe only the older ones could be dour but there aren’t many and I’ve never talked to any of them.
“Hey, Suze, y’wanna put itching powder on Janie’s strap-on?”
“Sure, let’s do it!”
Hmmm – I probably fit into the OP’s dour older lesbian category. There are certain situations where I automatically put on my butchest don’t-mess-with-me demeaner. For me, it’s one part protective armor and one part proud-to-be-butch attitude.
Having said that, you should see gathering of lesbians friends laughing their guts out. Some of us might be a bit dour in public, but I can’t think of any lesbians I know that DON’T have a hellacious sense of humor.
I am a hetero male who years ago lived across the road from a lesbian couple that I worked with. I used to spend lots of time at their place and going out with them because they had better taste in music and food than the people I lived with and they were much more fun to go drinking with.
I think if you look at most post-teen people on the streets it is disappointing how few smiling faces you see. Most people look as though they are going from a prison cell to the gallows. And it’s been that way for years.
Possible answer: Lesbian vs gay: who’s more likely to be approached by a stranger with “wanna have a three way with my husband/wife?”
My guess: because they can be. As others have pointed out, women in our culture are socialized to be outgoing, cheerful and perky. For many women, this comes pretty naturally. For other women, it’s much more of a stretch. Lesbians probably feel more freedom than heterosexual women to say, “Fuck that noise.” In my experience, doreen is also right that many lesbians seem to fear aging less than most heterosexual women. So they’re less likely to dye their hair, do Botox, or get boob jobs, which, in certain eyes, could make them appear more dour or serious than their chemically and medically-altered heterosexual counterparts.
Same goes for Lily Tomlin, Judy Gold, Margaret Cho (okay, she’s bi), pre-kook Rosie O’Donnell and so forth. 
The lesbians I have known have hardly been dour and humorless; they tend to have a kind of glittery-eyed & very wicked-fast sense of humor, saying hilariously sharp funny things, usually deadpan, to their friends as life & world rolls by.
They don’t tend to walk around with perpetual smiles on though.
My experience with women I’ve known to be Lesbians is very skimpy and I have to confess the gray short hair, dour expression thing hasn’t registered with me. I have noticed a number of very attractive girls in the company of somewhat older, hard looking, very “Butch” types, leading me to wonder why, if a woman wants to be with another woman, she doesn’t choose a partner who looks like a woman rather than a woman who tries her hardest to look like a man? I understand that question is flawed; obviously the hard looking Butch type HAS chosen a partner who looks like a woman. I guess I wonder why Butch types don’t hook up with other Butch types more often than they do? And vice-versa, of course.
But often a butch isn’t trying to look like a man.
Apparently my taste for jeans, T-shirts, not dying my hair (I don’t have any grey hairs, which pisses off many of my acquaintances enormously), sneakers and the discovery I made years ago that baseball caps are a good way to keep glare out while driving under certain light conditions makes me look masculine. Well, I’m sure it makes me look more masculine than my coworkers (several of whom have been coming with dresses right out of I Love Lucy)… but hell, I promise I’m not trying to pass for a dude, just trying to be comfortable! Nobody with these hips can pass for a dude.
Nava, straight for 40 years AFAIK
If you’re a straight guy in a gay bar, the patrons will be at least entertaining the thought of sleeping with you, which will make them glad to see you. If you’re in a lesbian bar, the patrons will be indifferent or annoyed that you’ll want to sleep with them, which won’t make them glad to see you.
That said, I used to know quite a few lesbians, and there’s definitely a subset you might call congenitally dour. But they don’t represent all, or even most lesbians. One of the most vivacious girls I ever knew was a lesbian.
Also, as burundi notes, lesbains don’t have to play the girl game to get laid, so many of them don’t. If your unused to that they may appear more dour than they really are.
Speaking as a woman who doesn’t smile like a cheerful moron when I have no reason to, I may very well come across as dour to others. I’m bi, not a lesbian, but tend towards masculine elements in dress and, frankly, I don’t care about impressing strangers that I have no interest in. If I find someone attractive or interesting or have some reason to engage them in conversation, I can be very animated and pleasant. If I have no reason to look happy, though, I’m not going to waste effort on this.
I rarely see two straight male strangers make eye contact with one another and smile in public, yet somehow because I have ovaries certain men expect me to be effervescent. It seems like almost once a day some strange man will come up to me and demand that I smile. I’m told to cheer up, that a smile would make me a pretty girl, that it isn’t “all that bad”, or any number of bafflingly retarded things, as though the fact that I’m not grinning vacantly implies I’m depressed.
Perhaps a lifetime of this could make for a bitter, grumpy middle-aged woman?
I wasn’t aware straight women needed to play any games to get laid other than “sit on bar stool. Wait.” Now, to attract lovers whom one finds especially desirable, then yes, some strategy is required, but I confess my ignorance of gay vs straight women’s criteria.
Shall we start a thread to get men to describe what attracts them to certain women?
As a somewhat butch lesbian (who does all the cooking and laundry in my relationship), I dress butch because that’s what feels comfortable to me - both emotionally and physically. I’m not trying to look like a man, I’m just being myself.
I’m also (generally) much more attracted to other butch women than I am to femmes. It’s not because they look like men, but because they look like strong women who aren’t afraid to be who they are.
It is extremely rare, in my experience, to see couples where there’s one definite femme and one definite butch. Rather, there’s a pretty wide range of dress and role preferences that pretty much defy any gender stereotypes.
ETA - my partner is quite butch too. Most of the couples we hang with, both women are more butch than not.
Ha! If you’re 22 and drop-dead gorgeous, maybe. Otherwise, it’s more like “make up, do your hair, wear the push-up bra, dress to play up your assets but not too slutty, look smiley and approachable, bring a friend along so you don’t get cornered by a creep, be friendly but not too friendly, laugh at things you don’t think are funny, and flirt with any joe that comes along.” And if you’re overweight or over forty, forget it. It always amazes me that men think that women have no problem getting laid.
All the negative attributes associated with lesbians int his thread? Straight women have to do the opposite. It’s not as if they’re born with uncomfortable shoes and highlights.
Women do all kinds of things to attract men; some are conscious, and some aren’t, but there are a lot of them. You think we wear high heels for our health? 
(I don’t wear high heels - they hurt.)
To your eyes my first sentence must have been written in white phosphorous, since it burned out the next bit: “to attract lovers whom one finds especially desirable, then yes, some strategy is required”
Against the embarassment of openly admitting my experiences at being rejected by women in their 40’s, I can in balance claim from authority that women can’t complain of being invisible to every man except those men who are invisible to to them.
I know - if nothing else you’d think this would give the lesbians in Doc Martens something to smile about