Thanks everyone for the suggestions. I collected the ones which subjectively seem best, here is the list for a quick overview:

• An open source discussion platform for communities.
• Lemmy, a decentralised discussion platform for communities
• Lemmy is an open-source social network that functions as a global web of independent forums
• A decentralized network of forums
• Discuss interesting topics and join communities on the Fediverse.
• A discussion platform that can’t enshittify. You choose your feed. You choose where to host your account.

Based on these suggestions and the discussion, the best option seems to be: A decentralised discussion platform for communities.

I will keep making more updates to join-lemmy.org based on this post and the previous one. Once that’s done I will likely make another post to show the results and gather additional feedback.