I've interviewed and been interviewed countless times in the last decade and maybe once I've worn a full blown suit. I don't have a problem with them, but I don't want to look like an asshole when everyone else is running around in hoodies and jeans.
I usually just step it up a notch from whatever the regular office attire is there (either by asking my point of contact or having known the office). If it's full SV/hobo style I'll do a polo and nice jeans. Business casual and I'll wear a nicer shirt and some khakis. If I really have no clue I'll go slacks and a dress shirt.
In my own office (we're all remote) I still wear jeans and a polo most days. Usually just out of sheer laziness.
Haven't worn a suit for an interview in decades. Last interviews, I wore a jacket and tie. I knew I'd be overdressing and certainly didn't need to. But it generally doesn't hurt to signal that you're taking the process seriously.
I've interviewed plenty of folks in the years since and they do pretty much the same. I'm not going to dock people because they approach an interview formally.
The only suit I've ever bought was for a funeral - and I question the logic in that (a rant for another day). Ive had about a dozen interviews over the years from small to very well known companies and I've always just put on jeans and a t-shirt, sometimes a jumper if cold. The only time I did not get a job offer was for a large travel firm in deeside, north wales. They interviewer asked why I thought it was appropriate to turn up to the interview in a t-shirt, my answer was kind of long and opinionated, as the two numpties sat there suited and booted talking about how awesome their company was. Needless to say that was one job I didnt get an offer for, however given that the interviewers were asking questions they didn't understand (e.g. how strings are managed in the CLR) I didn't lose any sleep. I later found out from others it was a shit place to work anyway.
I once interviewed for a job with a "hands on" recruiter clueless about tech culture who insisted I suit up. I overdressed and was interviewed by a VP of engineering who wore ragged cutoff shorts.
I usually just step it up a notch from whatever the regular office attire is there (either by asking my point of contact or having known the office). If it's full SV/hobo style I'll do a polo and nice jeans. Business casual and I'll wear a nicer shirt and some khakis. If I really have no clue I'll go slacks and a dress shirt.
In my own office (we're all remote) I still wear jeans and a polo most days. Usually just out of sheer laziness.