This was specifically about git. However, it does appear that you need to at least provide a user identifier for git. I can understand why that would be useful in a distributed system. It could be opaque identifier, but you're points taken in this case.

This was about git in the context of the GDPR, so a company (say, a git hosting provider) is by definition involved. If you're sending commits to other private developers in some way that doesn't involve a company storing the data, the right to be forgotten/right for records to be corrected/etc in the GDPR is irrelevant in the first place.