I'd argue that it's slowly happening, but maybe not with the handheld Ingenico or Verifone units popular in Canada, Europe, etc. In the past couple of years, I've seen more and more of the
Toast Go units in places around me (in the middle of Indiana of all places). It seems that the sit-down chains and more "formal" locations still opt for taking the card, but that might also be the cost of shifting to new hardware. A one-off or local chain can deploy a fleet of new units with their planned POS upgrades.
I think there are a few factors involved:
1. Wireless terminals (at least from traditional players) still being way more expensive than they should be--especially since chip and signature makes them not strictly required.
2. Online shopping being way more of a thing by the time the US finally transitioned (vs. a lot of other places). That effectively made stuff like paying online in advance (e.g. for pizza delivery) and QR codes on restaurant receipts more viable than they would have been elsewhere.
Those seem to explain the following that I've experienced, anyway:
1. Pizza delivery generally NOT having wireless terminals at all. You either pay with card online at the time you order, or cash when they arrive.
2. Restaurants generally not having pay at the table (or if they do, it's either a QR code thing or something like Toast or Square geared towards smaller restaurants).
3. Various tradespeople (plumbers, etc.) accepting cards, but through some sort of tablet or phone without a card reader at all. i.e. they basically put your card number in like it was a payment on a website, even if it's a custom app they're running.
Additionally, speaking of (1) above, even the savings of running card present instead of card not present might not justify the extra expense. Especially if customers complain about it and expect things to happen "like they always have".
Note: as with a lot of US stuff, YMMV.