@Ghostalmedia@deadsuperhero I think the fact that I was able to see and reply to this comment of yours from Mastodon proves this idea false, if you check the Post history of this account you will also find that content posted in Lemmy is visible.
They absolutely do interact, lemmy is way more Mastodon friendly than most people give it credit for, considering the fact that communities/groups, automatically boost every post and comment for visibility.
So people on Lemmy being concerned about poorly moderated or cesspool microblog instances is indeed a valid concern.