I wouldn't worry about Lemmy having as many users as reddit in the short term. Success is not just a measure of userbase. A system just needs a critical mass, a minimum number of users, to be self-perpetuating. For a reddit post that has 10k comments, most normal people only read a few dozen comments anyways. You could have half the comments on that post, and frankly the quality might go up, not down. (That said, there are many communities below that minimum critical mass at the moment.)
Lemmy is now a real alternative. When reddit imploded Lemmy wasn't fully set up to take advantage of the exodus, so a lot of users came over to the fediverse and gave up right away. There were no phone apps, the user interface was rudimentary, and communities weren't yet alive. Next time reddit screws up in a high profile way, and they will screw up, the fediverse will be ready.
Lemmy has way more potential than reddit. Reddit's leadership has always been incompetent and slow at fixing problems. The fediverse has been very responsive to user feedback in comparison.
Lemmy has enough user activity to fulfill my time-wasting needs.
There doesn't need to be one website that EVERYONE is at. The Web didn't used to be so damn consolidated.
I don't give one shit about "Lemmy vs. Reddit". I care about Lemmy having active communities to engage in, regardless of what is happening on some other website.
Yes this is my thinking as well. Before reddit I was more than happy participating in forums on subjects I enjoyed. I had want I wanted. I almost have that here as well. That's success in my eyes.