In my case, I'd actually quite like the comments to be left in, one of those is my personal key, one is for work. Differentiating is useful depending on why I have access.
Certainly, but your user@host will be leaked to the staff of Github / Gitlab and to anyone that compromises your account. The unfortunate thing about anonymity is that a small mistake can be costly. It depends what your threat model is, though.
https://github.com/Lattyware.keys - GitHub leave it blank:
https://gitlab.com/latty.keys - GitLab add a generated comment: In my case, I'd actually quite like the comments to be left in, one of those is my personal key, one is for work. Differentiating is useful depending on why I have access.