One of the instance that is promoted on join-lemmy.org is burggit.moe that is defined as “NSFW & Loli/Shota/Cub friendly”. Loli is legally considered as paedophilia in europe and the US, so even if it’s legal in the country that host the instance, I would suggest to not promote it as an instance to join
The devs certainly won’t. The main instance doesn’t get moderated… regrettably Lemmy doesn’t have the dev and community support that the other federated tools do.
You can check the mod logs, they are public and there’s a link to them at the bottom of every page. I have certainly seen the mods of lemmy.ml giving out temp and permabans for rule-breaking behavior. I have even seen them hand out lengthy (4-5 day temp bans) to users who seem to post content that is much more closely aligned to the lemmy.ml admins world views than the other party in the conversation leading to the ban. I think the accusations you’re making here are pretty off base.