We saw lots of this during the big Reddit migration a year ago. Personally I'm not a fan at all - I feel like it just floods mostly empty communities with posts that get barely any interaction. Any posts made by actual people get lost in the flood.
If I open a community and I see a handful of posts from people over the past few weeks, I might check them out, comment, maybe subscribe and contribute something. If I see a page of posts from a bot, mostly with no comments, I lose interest. And that was definitely something I ran into while first exploring Lemmy a year ago.
I'm not 100% against all bots - for example, something making daily posts might not be so bad.