His argument comes down to "Bitcoin can do it, why do you need another coin?"
Because as Satoshi said: "Piling every proof-of-work quorum system in the world into one dataset doesn't scale."
https://bitcointalk.org/index.php?topic=1790.msg28917#msg28917
RE: The Price of Steem - Where Do We Go From Here? Reflections by Charlie Shrem