Setting up and managing keys, spinning up new repos, etc. would suck up an inordinate amount of time. This was especially true when I worked at consultancies. Blocking developer work with “Sorry gotta wait on Todd to add you to the server and set you up on Git,” when Todd would avoid it like the plague because it sucked would lose a lot of time.

If you averaged the time out, it may not have hit the five hour per week mark, but it combined with other time savers (linking Git directly with the issue tracker for example instead of having to figure out how to cross reference them) easily did/does.

Maybe not managing permissions directly. But I could easily see a number like that, or higher, being plausible if you consider clean up from junior devs accidentally pushing to development/main branches thinking they were on their feature branch. Which is an issue directly solved by permissions.