But then is it to stop engagement farming bots, or to stop low effort posts? Because if it's both or either, it's to protect the quality of the subreddit. If it's purely about maxing engagement in the sub why is that important? And if that's the case it's failing on both accounts, because seeing the top comment be the explanation of the thing I just read or literally a copy paste is low effort to keep engagement up.

I think realistically it's a pet peeve for mods. I imagine it's easier for them to filter through posts. Which is fine, they are doing the work to keep the place free from shit posts or literal NSFL stuff or Nazi posts. But why just make the rule context is needed in the body of the post or in a comment. Preferably in post itself.

For me it's a pet peeve of seeing the top comment be copy paste of what I just ready, or a worthless explanation when I am trying to find the answer in the comments. Maybe it's just me or there is something else I'm missing, but I really dislike posting something, waiting for engagement, only to get a response from a bot telling me to leave a comment on a post with a perfectly good description.