Lemmy is very much a viable alternative
Oh, how I wish that were true. Alas, stats keep showing that Lemmy is not continuing to grow, on the contrary. There is close to zero activity in anything but the most main stream communities and Lemmy is only now making very, very slow and tentative steps to actually surface more niche communities after effectively burying and suffocating them in every release up to and including the current stable.
That’s not what I use Reddit for and that’s sadly the only Reddit (and other social media) thing today, that Lemmy mimics successfully.
I’m using Reddit mostly for the niche and special interest communities. For specific tech advice and troubleshooting. For all the stuff that once used to be home on newsgroups and bulletin boards and can now only be found in subreddits and, even worse, Discord communities.
And a lot of these smaller tech communities were super motivated to move to Lemmy, but Lemmy’s complete inability to surface anything but the most popular posts in the most popular communities (there’s still no equivalent for multireddits and there was no weighted popularity until 0.19) rapidly killed and suffocated virtually all of them.
That’s the reason why you can type “obscure technical problem Reddit” into Google and almost always get a relevant answer, while that will likely never be the case for Lemmy.
I’m not saying Lemmy doesn’t have good communities, it certainly does, but once you go beyond news, politics and memes there’s neither enough content nor enough users to keep anything else alive.