I see this comment every now and then, and it always forgets the cost of the transaction, confirmation time, and of course, the need for miners to exist to process these confirmations/transactions. The energy cost is extraordinary, and the end user is taxed for the use of their own dollars.
It’s not really feasible on a broad scale. Bitcoin is a holding stock, not a valid currency. Its value only increases because it manufactures its own scarcity. And as its scarcity increases, it naturally moves toward centralization since mining becomes too large an activity for the individual to reap any benefit. You can argue for proof of stake to eliminate the need for mining, but then you open the doors to centralization more immediately.
It is also worth considering that yes, MS and Google have definitely dominated the market through superior products, but the standards they’ve pushed for and established have also made it difficult for other players to enter. If we wanted to say that the federated nature of email is dead, I think that’s a fair argument still.
Hosting your own email server is quite difficult. You have to jump through a lot of hoops to land in anyone’s mailbox without assistance. If you want to make a mailing list, you basically need to use a mailing service, lest you get blacklisted by major systems owned by MS and Google. Much of this is a byproduct of spam, by which I don’t blame Google and MS for doing their best to protect against, but at the same time they have more or less neutered some core aspects of what made email accessible.