For a more user-friendly (IMO) alternative, altough not open source, there is Resilio Sync. The main difference with Syncthing is that you don’t introduce clients to each other; you just share folders.

When lemmy.world will disappear, that’ll be a lot of communities (and valuable information) that go with it.

Technically it’s wrong.

You’re not good because you’re afraid of the consequences of being bad. You’re good because you have empathy and know that kindness is overall better for everyone (you included) than nastiness or immorality.