A large fraction, yes, but I believe in absolute numbers, US issuers still retain much more interchange than European ones.

The numbers are even public: https://usa.visa.com/content/dam/VCOM/download/merchants/vis...

If you take a look at some of the more "expensive" cards, interchange is often higher than 2%, yet issuers often pay as much only on certain categories, and flat cashback cards usually pay 1.5% (2% is relatively rare).

Compare that difference to a total interchange of 0.3% in the EU.