…Because what with underscores in user handles, and the overall look and feel, it’s like being transported back to 1997.
That is all.
When I visited Stonehenge, I felt much, much younger. 
Well when I visited Java, I felt even younger than that.
What can I say? Youth is overrated.
I realized there’s a reason why user names can’t have spaces or most other punctuation marks. It because you can mention a user with an @ and that breaks if the name has spaces or most other punctuation marks in it. For example, @Spectre_of_Pithecanthropus works but @Spectre of Pithecanthropus would not work (or worse, might refer to a different user, which I think actually happens in this example).
Ahh. That makes sense though it will tend to spoil a lot of great user names. If I’d known that spaces would one day be disabled, I wouldn’t have chosen my handle. Such as it is I’ll keep it.
ISTM this is basically Twitter’s fault.
Facebook makes @ happen with spaces in names…and frankly it’s maddening. It’s like the whole service is focused on making sure you tag people, so that when you’re just typing a nonsense post on your wall, for every word it’s suggesting the name of some rando in a group you belong to. Yesterday I was saying something using the word “day” and it suggested some asshole’s name that got into a fight with me on a private group two weeks ago. Do not want.
Maybe it’s Twitter’s fault and maybe it seems like an ancient practice but it seems better than the alternative of following your cursor around waiting to suggest a name. And the tagging feature is neato…seems like for years people thought that posting “Paging QtM!” called a doctor. Now we can actually summons him 