I think, because it's a new platform that most of us want to see succeed, everyone is far more active to ensure the communities get established. If there's a couple of days without a post in one of the 3d printing communities I subscribe to, someone will post a random print they find useful or ask a question about a new filament to keep it active. This low stress discussion is great.
The 3d printing community on that other site ais great, but sometimes it feels like posts don't gain traction unless it's on a 1 cubic meter Voron that can print PEEK (translation: very expensive/unique). On the Lemmy communities, there's more discussions on Enders and Anycubics (translation: most common budget printers).
I took note of it before I left. Other people mentioned it. I didn't think it would be as big as it was. Kinda cool. Never cared about it enough to check.
Yeah I've genuinely not missed it, been just over two weeks and I've been having so much fun here I haven't once found myself at a loose end wondering whats happening on Reddit
Which is surprising considering i still run quite a few subs I started and mod a few medium sized ones, when I get back home in a couple of weeks I'll convert my bots to message me via lemmy instead and I really don't think I'll be going back