Agree to disagree.
This is true. Those people suck.
Personally, I handle situations like this (with bosses, coworkers, or when maintaining peace is paramount) with passivity and avoidance, until I can permanently escape. 
With friends, family, or when peace comes at too high a price, I get aggressive and call them out. (“Aggressive” for me means having a forceful conversation, not getting violent or destructive.)
I certainly appreciate someone who has the courage to say what they actually think rather than someone who wants to get their point across, but still have an escape hatch so they can pretend like they aren’t behaving like an asshole. My brother’s wife is passive aggressive and the technique that works with her is to straight up call her out on it; just react as if she had explicitly stated what she passively implied. She’s still a jerk, but she shuts up more.
Sorry, can’t edit – let me clarify in post #20, that I would vastly prefer that whoever has a problem with me approach me early on about my problem behavior, in a spirit of good-will and cooperation, so that I can learn what I’m doing is wrong and correct it now before it gets out of hand. I’m a well-meaning person who doesn’t want to disturb anyone, so I probably don’t realize my behavior’s a problem but would appreciate it being pointed out to me (calmly, civilly) so I can change it.
And then, far far below that option, my #2 preferred option is an angry confrontation. And then exponentially farther below #2 is passive-aggression.
The passive aggressive part is when the passive aggressive people get around to firing the person who smells bad, it’s all “it’s not you, we’re just having a slowdown in the business, we’re sorry to inform you that we are laying you off…”
a straight up “wow you smell bad. Bob, go take a shower. come into work smelling like that again, and you’re fired”.
And if Bob comes to work smelling bad again, it’s “Bob, you’re fired”. None of this passive-aggressive crap.
And countless more examples. I would prefer if people were honest with each other, even when they have to do something that is bad for the other party.
To my mind, the really passive-aggressive response to the bad smeller is not avoiding him or getting rid of him - it’s something like going and working at a nearby desk and then suddenly looking up at a completely different co-worker
“Hey Joe. Drains sure smell bad today, don’t they?”
“sniff sniff Sure do Charlie. You reckon some critter just died under the floorboards?”
“Funny thing - I never really smell that dead critter before everyone’s at work in the morning”
“I sure hope that dead critter’s gone by tomorrow”
Now THAT is passive-aggressive
The acceptable response is assertiveness, not aggression, in most cases when passive-aggression is used. The point of the term is not to say “I’d prefer you to be aggressive.” It’s to say “your passiveness is really a form of aggression.”
That doesn’t mean some people might not prefer aggression–at least, in limited form. (I don’t think anyone would prefer rape or murder, for example.) But that’s not the point of the phrase.
I find that to be a helpful perspective.
Yes, but so could be avoidance–if that avoidance is hurtful. I agree firing them would not be passive aggressive. It’s just hiding the real reason.
As I define the terms, aggressiveness is hurtful. Assertiveness tries to lessen the hurtfulness. Passive aggressiveness maintains the hurtfulness but tries to create (often barely) plausible deniability. It’s being hurtful while being less directly confrontational.
Like, with your example, the people talking are ostensibly talking about something else, and directing what would still be aggressive if said to a person towards the drain or the floorboards.
But you can also do it with avoidance. You can pretend not to hear what they are saying, or do other things to make it known that you are avoiding them, while still creating that plausible deniability.
I can’t really see firing them as being passive aggressive, for the simple reason that you are completely avoiding telling them what was wrong. Where’s the aggression? Firing someone is not inherently aggressive.
I do wish to add that assertiveness often involves trying to be discreet. It’s not inherently direct, and it intentionally tries to avoid being confrontational.
It’s still assertive to tell the smelly person looks like they’ve had a hard day and could maybe use a shower. Sure, you’re not being completely direct, but you’re also trying to remove the hurtfulness. Similarly, you can take your boss aside in private instead of directly contradicting them in front of everyone and making them lose face.