It's indeed a good move, but fiat-crypto pair usually involve KYC and many people still want to trade anonymously so BTC pair still has its use.
But if fiat-crypto is still using some kind of tether, well.. it sucks
Having both option can be good though

What are telling is true that if you want to trade in fiat currency then you have to fulfill all KYC documents then automatically it will become like you are trading in stocks. then i think the main aim of cryptocurrency formation will die of decentralization with out relieving identity verification.