Remember, Lemmy has a lot less active users than Reddit. Even if ALL active Lemmy users on Lemmy.world buy the app at its original $2 price, it's still not enough to sustain full time development. Both higher one time purchase price and subscription is needed for the app's survival, even then I'm still not sure if it's enough for the dev to sustain themselves. I'm getting the ultra subscription for this reason because I don't want the app to go away, and I encourage people that really like the app to do so as well.