Here are some mod logs from lemmy.ml (which is an instance run by the Lemmy devs) from a few years ago: https://raddle.me/f/TankiesGonnaTank/89852/the-lemmy-ml-admin-is-banning-anyone-that-mentions-stalin-or
Here's one of the Lemmy devs (you can tell it's them from their profile activity) denying genocide: https://old.reddit.com/r/MapPorn/comments/xq49ct/deleted_by_user/iq954mu/
Insisting that fascists are good, actually not fascists at all, as long as their nationalism makes them oppose the US (because the enemy of my enemy is a totally good guy!): https://old.reddit.com/r/DebateCommunism/comments/vgg2x3/thoughts_on_slavoj_zizek/id2cxb8/
There's more here: https://raddle.me/f/lobby/159606/-/comment/294792
But are you suggesting this somehow impacts Lemmy? It's an open backbone that anybody can use to create an instance - in fact, by default each modlog is open, could you do the same and link the moderator actions /u/spez took in 2018? Could you create your own Reddit and defederate half of the content if you wanted to?
As I see it, Lemmy's creators made their own instance to share their political views - that's it, of course they control the rules over there. They also made their technology public so that I can type out this comment on Lemmy.world, which follows a completely different set of rules.
I guess it kinda matters in that people like me certainly won't be giving any code contributions, which for an open source project can be critical to its long-term health.
But devs also tolerate and use tons of code and the licenses that Richard Stallman wrote, even if he's a huge creepball that a bunch of other free software orgs had to back away from.
So we'll see. I also wouldn't rule out a fork of it just so that it's officially ran by a less controversial group.