Lol. I left Reddit for Lemmy, and I continue to use Lemmy. I am very much the exception and not the norm, though.

I will be very, very surprised if Lemmy ends up growing more popular than Reddit at any time in the near future. As others have pointed out, Lemmy's popularity has been decreasing and Reddit's popularity has not substantially decreased. There's still way more people and content on Reddit than there is on Lemmy, and I don't think there's any evidence there was any real mass exodus. Some people left, but it was basically a rounding error in the grand scheme of things. I would expect the same even if Microsoft, Tencent, Activision, or pretty much anyone else were to buy Steam. People may get irritated, and some people may even leave and never come back, but most people generally want to just continue using the services they're used to.