It is a simple matter of having current and relevant knowledge for the role. Would I hire a junior developer who didn't know much or even anything about using g

It is a simple matter of having current and relevant knowledge for the role. Would I hire a junior developer who didn't know much or even anything about using git? Probably. Would I question the seniority of a so-called senior developer who didn't know the basic usages of the most dominant source control tool for the past 15 years? Absolutely. If they had a good explanation for that gap in knowledge, like working for the past 20 years somewhere that was stuck in legacy code and running on SVN, I'd definitely take that into consideration. I might still want to be certain this candidate is smart enough to quickly pivot into a new codebase and new tools. I've met many people who struggle with exactly that kind of change which is exactly why they don't keep their knowledge current. I'll admit that asking people how git works isn't a question I would ask in an interview. Playing devil's advocate though, I would probably not hire someone claiming to be a senior developer who doesn't know how git works.