I think it's more than just number of users. We have the possibility of infinite clients, each with their own ability to cater to our needs. With X, you get what they feed you whether you want it or not. You have merely an illusion of control. They will ultimately feed you whatever pays the most in ragards to THEIR goals.
In theory, I can choose to the smallest degree what I want to see on #Nostr. And I think it will only get better with AI tools, more clients, etc.