There are unfortunately some subreddits which are still the best place to find timely info about certain topics - for example video game subs run by the developers of the game. Lemmit is a way to subscribe to those while not giving Reddit any more “engagement” or ad views.
The bot that runs Lemmit only posts on its own instance, so users like me only see it when we subscribe explicitly (or the All view I guess, but that’s a mixed bag already. Edit: and each user could choose to ban it if they want)
If the bot was adding to the already taxing load on the lemmy.world server, how is it fair to those wanting to make this place anew rather than regurgitating reddit posts. In my (possibly unpopular) opinion, if you want to see stuff on reddit, find an alternative method that won’t inconvenience others.
I can’t speak for the admins, but my guess is that since only Lemmit communities that lemmy.world users subscribe to would be replicated here, it might not make much additional load. Also there isn’t much voting or commenting on those posts.