talent and the capacity for determined effort, sometimes called ‘grit’, depend a great deal on one’s genetic endowments and upbringing.

Someone wanna tell me what they could be based on other than genetic endowment and upbringing? Is there any factor that isn't encompassed by those two categories? The unknowable will of the Flying Spaghetti Monster?

Meritocracy is not only wrong; it’s bad.

Meritocracy is the worst option there is, except for all the other options.