I believe one of the major setbacks of the present crypto space is a lot of new projects are focused on providing the fastest easiest crypto coin to be used for payment purposes and transactions however considerably lower effort is placed on the vendors who are actually going to be accepting payment in form of cryptocurrencies because what is the use of having a crypto payment card full of money that you cannot spend.
Whitmore payment gateways a inform of PayPal and the likes accepting crypto payments from multiple coins without necessarily issuing their own coin then there will be better adoption of cryptocurrencies by both business owners and customers.
I think somebody will create (as there already is in market ) easy plugins for merchants / POS terminals and stuff like that to accept crypto . And it will not matter with what crypto you pay ERC / BITCOIN or any other coin/token . As long as it will have value , it will be accepted .