Eh, merchants have long been complaining about the squeeze from the credit card networks, which routinely raise percentage fees. And merchants have to raise prices for all consumers to keep up.
A fast, free alternative to those would certainly provide some relief.
Cards do not compete with ACH or FedNow. Cards are intentionally reversible and non-final. They serve a different need and use case.
People want insurance products, they want rewards, they want chargebacks and they want to borrow up front - and so do merchants. It increases average ticket sizes and it saves them from having to deal with cash. This system didn't get foisted on anyone, it was built to meet the needs of both buyers and sellers.
In Europe where interchange is regulated, credit cards are capped at 0.3% interchange but don't come with those features.
It is kind of interesting how some cryptocurrencies like Solana or Stellar could in theory outcompete PayPal, Visa, MasterCard on fees but the volatility of the underlying cryptocurrency makes them uninteresting for businesses.
A fast, free alternative to those would certainly provide some relief.