> But for the tech jobs most people want, it's a really bad idea to put a suit on for a interview.

Why? Are you saying that some company will give you a hard time because you are wearing a suit? That would certainly be humorous.

Humorous as in "Haha, I have no intention to work in such a place, ever".

I'm not in industry, but in CS academia interviews seem to be the one holdout where people do usually wear suits. People attending conferences don't (except in Asia), professors don't, the department chair doesn't, the interview committee themselves probably won't either, but there's a ~70%+ chance that someone interviewing will. Or at least a sport coat and slacks (I guess not technically a suit, but close enough). You probably don't really have to, but people tend to err on that side for an interview in an unknown setting.