It makes more sense to rename the account. In the case of a user having old photos, likes, or comments, they don't lose all their history.

Another HN commenter had a similar experience: https://news.ycombinator.com/item?id=7598567

Yes, but they didn't say they would do that, they said they would remove them - although the ToS probably doesn't give the offended customer any recourse, and the fact that the service is free means they have no leverage to challenge the ToS in court. The lesson here is that if you're not very busy and you have a name someone else wants, it can be taken away from you.