And as it grew, it became a more attractive target for zealots, propagandists, and trolls. And as it became a larger community, it became - to some degree - a diluted one.
Metcalf's Law says that the value of a network is proportional to the square of the number of users. V = k N^2.
AnimalMuppet's Law, which takes into account the greater attractiveness of larger networks to those whose activities destroy value, says that you must subtract a term proportional to the fourth power of the number of users: V = k N^2 - K N^4. Depending on the values of k and K, there will be some optimal number N of users, beyond which the value stops growing - or, beyond which the value to each user stops growing.