I think, at least in sfbay, it's safe to assume git. And probably some CI tool. This is true across my personal sample of perhaps 15 companies that I know well enough.
The Bay Area is better than most places, but the moment you aren't dealing with a purely software shop, the probability they don't have this stuff goes through the roof.
The PCB design tool Altium only has provision for using Subversion (which is fine, thanks), but the number of people who actually USE it is miniscule.
I think, at least in sfbay, it's safe to assume git. And probably some CI tool. This is true across my personal sample of perhaps 15 companies that I know well enough.