I think it depends on a lot on the studio and culture. I don't think I saw a single unit tests before I left gamedev(a few smoketests to make sure the game didn't crash but that was about it).

I also rebuilt our audio streaming system over the course of 48 hours to use the texture streaming subsystem when we exceeded the 64 file handle limit on an certain platform. We needed to hit a date for a TGS demo and I can guarantee you that we had things which were even more YOLO for a fairly decently sized team/game.