Wonderful essay - and beautifully written, as well. Much to think about.
I think a complementary set of forces might concern the increase in the bargaining power of the masses brought about by liberal modernity, coupled with the fact that most status competition in well-governed liberal societies is over prestige (respect and admiration) rather than dominance (bullying, force, and intimidation). So, ambitious liberal elites partly channel their ambition through competitive altruism and egalitarianism. Put simply, being an egalitarian has a higher status payoff in this kind of context than being an elitist or simply not caring much about equality. This is a more cynical analysis than this essay’s thesis, but both kinds of forces might co-exist and reinforce each other.