Allowing the maintainer to prepend a comment to the top seems more sensible to me to be honest. Would make API use harder potentially, but it would avoid weird abuse like this.
hmm... isn't this more of a 'personal viewpoint'? why are you stating this like a fact?
moreover, how would it "adding Edited by ~" constitute as a "loss for everyone" ?
I agree on adding "report abuse" button, but if no one notices that edit, how would anyone know what to report in the first place?
Normally, repository maintainers are not self-sabotaging like this.