That’s a great answer. My observation (watching from a card issuer across the pond) has been that it’s also integrated checkout/POS infrastructure at a number of large retailers - supermarkets, department stores, pharmacies as well as automated fuel dispensers and ATM†. The USA lagged for probably 15 years before there was any significant penetration of chip + PIN and contactless payments. Once the first large retailer replaced its fleet in ~2017 it’s been accelerating.

Since the USA makes up fully half of global card payments, MC and Visa were never going to ditch mag stripe until there was 80% penetration.

†Many AFDs seem to be configured to reject international cards which may explain why they’re not well represented in my sample set.