I still use Reddit to read a few niche subreddits, and I'll search there for answers to older questions (because over the last fifteen years, pretty much every "how do I fix this" question has been answered somewhere there), but it's no longer a place I post to.

I never used HN (other that when someone shared a link elsewhere), so there was nothing to give up (and honestly, I'd thought on first learning about it that SN was just "Hacker News with Sats," and didn't realize just how much deeper it was, even before taking actual content and users into account).