getting a million sign ups on a corpo social media thing is "good" because it means you probably have enough critical mass and enough user data to start selling advert slots, so you can sort of sustain yourself that way; in that sense, you've "made it" because barring catastrophe you've reached a point where you can maybe break even for a while

getting a million sign ups on a fedi social media instance, by contrast, is prettymuch just bad because you can't sell advert slots, and suddenly you're facing huge costs in terms of hosting and moderation; you haven't "made it" because you can't leverage those numbers for anything except bragging rights or making vacuous claims about how the fediverse has become "mainstream" or whatever

So "making it" in corpo social media and "making it" in fedi software development are basically opposites, because reaching "sustainability" in one looks completely different from reaching "sustainability" in another: the criteria for success on that front absolutely do not map from one to the other. I wonder if the "line goes up", "user numbers above all else" aficionados will realize this at some point.

Imo "success" in open source software dev basically means you've made something semi-useful that doesn't suck too much ass, and you can afford groceries and you like doing the work. Large user counts are irrelevant if not actually harmful to this.