You're right, no reason to comment on their post like a human and suggest edits. Better to sic a bot on them because you know more than the person making their first post.

Maybe their second post becomes a true introduce yourself? Maybe they learn from seeing few upvotes on a post?

I've considered the things you are saying already. People, however, have free will.

My approach will be to teach them how to edit their posts our make new ones better. Keep doing your righteous downvotes.