You're almost describing the lightning network, which depending on where you get your numbers can handle around 10-40x the transactions per second of Visa or Ma

You're almost describing the lightning network, which depending on where you get your numbers can handle around 10-40x the transactions per second of Visa or MasterCard, neither of which are above 70k in anything I found with a quick search. Granted it sounds like the lightning network has other issues.