There is no reason for a bot to be able to access or post on federated social networks if the goal is to make social media humane.
For this reason, bots should be heavily disallowed from posting content to or accessing content from federated social media.
Often a user is interested and knowledgeable in the topic they’ve posted and will reply to comments, creating dialogue and new content.
Now that is an interesting point and definitely a point against bots. Ultimately I think it’s still OK for them to post, but you’re right that a genuine seed conversation can be helpful to get the whole post started.
I know in Reddit times some subs required a submission statement and that was a positive. I think if such a rule were adopted I’d be ok with limiting bot posts.