Ethereum is increasingly becoming a fiat payment platform thanks to the plethora of stablecoins that reside on top of it. Tether's $4B in coins have mostly migrated over from the Omni protocol. All of the next few biggest stablecoins are of the ERC-20 variety, including the new Binance once. Then there's Dai, the first ever decentralized and uncensorable digital dollar. It's early days, but stablecoins may have already surpassed Venmo in quarterly volume of dollars moved.
It's only a matter of time until "fiat on the blockchain" becomes a dominant force in payments. Yes, these products are new and clunky, and the networks they ride on are slow and have scaling problems. But so was every other payment method in its infancy. What matters is the long term potential, and there stablecoins have a lot more to offer, because an open network always beats out a restricted pipe.