In my experience (some games in z80 and 68000 in the early 90s), version control wasn't considered until mid-90s sometime, and at first wasn't trusted. There were network backups, but I don't know if they had revisions.

Merging seemed like it couldn't possibly work well, so we would try to have separate ownership of different files. Although there would be only a handful of programmers on a team, so that was easy.

Prior to that, backup and versioning was manually handing a floppy or two to someone each week.