For those who work in the dark matter of the industry, there are no real resources because most places don't even have "question banks". When an interview request pops up on my calendar, I just go out and find a random question - it's totally disposable and unlikely to be used again, and we don't interview enough for someone to compile enough information on us.
None of the places I've interviewed at in the last 5 years are on this list. One of them has a single question reported on Glassdoor and wasn't similar to what I was asked.
Bigger companies do have question banks. Finding a random question at interview time makes it (1) difficult to compare across candidates; (2) makes the interviewer work too hard since the interviewer hasn't first thought about the question and makes the hints given to candidates less useful.
And Google, being the maker of a search engine, was good at detecting leaks of their questions.
I work for a large company that hires a lot of developers. If you're in the US you've heard of us and there's maybe a one-in-three chance you're our customer. We are not "sexy" though. I have seen question banks circulate occasionally but when it's time to actually interview nobody can ever remember where the question bank is. Usually when I've been on a team that's actively hiring we make up a bank of questions for that particular round of hiring, which helps us in comparing those candidates that are directly competing against each other. But nothing at scale.
Yes, question banks exist. I'm talking about the company I work for and in fact all the companies I have ever worked for. We did not use question banks.
Your claim was most companies though but to be fair, you are more accurate.
Most of The big tech companies that are viewed heavily on levels.fyi definitely has question banks.
Most software engineers work at companies with names the average person wouldn't recognize. Like, some random B2B company in Ohio that manages corporate gift cards, with 100 total employees. Multiply that by a million. These companies may come up on Glassdoor, but there won't be enough posts to get any kind of consistent pattern on how they run their interviews.
None of the places I've interviewed at in the last 5 years are on this list. One of them has a single question reported on Glassdoor and wasn't similar to what I was asked.