It's probably important to note survivor bias.

Every Mage society worth portraying has survived to the present day of your Chronicle (for Time-Arcanum-given values of "present day"). That doesn't mean that most Mage societies have survived: it means that most of them didn't work out and imploded in one manner or another. The structure of the Big Three sects exists because it works. The Lex Magica and the Iron Pyramid are a big deal for precisely that reason.

The other trick is that Mages are relatively rare. Forumites like to debate the exact numbers and ranges,...