It's the Team Fortress 2 paradox all over again. TF2 famously had a number of games all coming to dismantle its market dominance and each of them failed miserably. This might have seemed puzzling given TF2's somewhat antiquated gameplay and maps. It turns out that the magic sauce of TF2 was never the gameplay but instead the dogged and disciplined developer support from Valve over the years. For the latest example, look no further than Overwatch 2 killing itself with a greedy business model which, again, had nothing to do with the core game.

Likewise, Twitter is a very simple website to clone and compete with. Resisting the temptation to censor, putting in the effort to establish a non-exploitative business model, etc, is something that no one else has been able to do.