> I think most open federation / blocklist servers cannot be locked down adequately to protect (inexperienced) users from seeing horrifying things, receiving harassment, and other age-inappropriate stuff.
We use the CARIAD list from IFTAS, and it works great. I cannot remember the last time I saw harassment, grossout photos, or other terrible stuff.
You can also set a Mastodon server to allow-list mode, which might be better for this kind of thing.