I'm afraid most US chains/restaurants will only change their equipment when their equipment dies. It's going to be a few more years to a decade I think. Most of these units are pretty reliable and can go for a decade or more easily. At least most POS at gas stations, chain stores take NFC now.
Tap phone, confirm payment, tap fingerprint reader to confirm.
vs
Try to flag down waiter (x5), ask for the bill, wait for waiter to return with the mobile POS, fiddle around in your wallet to find the card, tap card, decline tip, write PIN code, finally get to leave.