sorry correction if I am wrong in opinion, it looks like sending bitcoin or altcoin on the exchange has been implemented, where all users and traders can send their funds or make transfers to other users as long as it's in the same exchange, what's interesting and great about this, if One day, fellow coinbase users do bitcoin transactions using email, I think it is not a difficult job because they have funds deposited in the same wallet, to be exact a coinbase cold wallet, except to transfer bitcoin to an email address that is not a coinbase user maybe it will cool, even though I don't have a coinbase account but there are people who send bitcoin to my email, of course I have to register a coinbase account to claim bitcoin, hopefully I am wrong