I admit I wasn't intending to leave Reddit. Sure, I absolutely wasn't going to install the damn official app, but I browse Reddit way more on desktop that on my phone. But it turns out my time spent on Reddit absolutely tanked without me doing much. Lemmy turned out to be a better replacement for me than I expected, I could find a lot of interesting activity here unlike, say, Mastodon where I had to dig further.
That does not mean I left Reddit entirely lol, but I sure enter way less now.