It won’t ever scale to a real global default social network, on the donations and the kindness of strangers

The issue is: I don’t think people are bothered enough with commercial social media to the point of paying for an alternative. Think about it, even with the majority of Fedi instances being free to use, not many people stopped using Twitter/Reddit/Instagram. So I think Fedi instances need to be free to use while it’s small to attract new users.