Because according to popular judgement, independent email hosting in the modern day is a very difficult ordeal.

Is that true? Is that false? How would one tell? One's own experience will be trivially handwaved away as an anecdote, people's experiences will be handwaved away as hearsay, and a claim of general consensus will be handwaved away by other claims that the person pointing it out is just living in a bubble. Principled thinking? Could be false, could be true, really - both would make sense. Doesn't sound very productive to discuss to me.

If nothing else, surely you can agree that despite what might be, what is is that email is incredibly centralized, right?