My company does an IQ test for interviews, but I rank it among the top places I've worked at in my career. Do you have any evidence that IQ tests are only done by companies that are bad places to work at?
It's the other way around. I've worked for a company that did (de facto) IQ tests before hiring. It was great. Everyone was intelligent, thoughtful and efficient and the company was successful. The problem was the owners (who of course had not taken any test). They were a mix of crazy and stupid, and the staff had to continuously work around them.
I don't think I would ever work for a place that required IQ tests because that would mean that they didn't not just understand the racist and ableist origins of IQ testing (which is a red flag for an employer, imo) but they also were ignorant of the fact that they don't actually tell you much. Using IQ tests as a meaningful way to measure intelligence has long been debunked by academics who study intelligence.