Is Lemmy resistant to any of this, or is its future child porn etc…

Can you though? There have to be communities to join, and they are what get polluted. As I understand it, switching instances won’t help.

Someone then has to police a community if you want to “get rid of the riff-raff” and they will follow who-knows-what criteria for their policing. Just look at all the right-wing subreddits for an example of how policing doesn’t necessarily raise the quality of discussion.

Frankly, I think it’s entirely because of the self-selected nature of the people migrating, and the fact that the whole federation thing is mildly confusing so only people who have made sense of it and worked out how it works are here. If/when it becomes more obvious and popular beyond early-adopters, it’ll be targeted by all the same bots and propagandists and chudiots as anywhere else.