Updating an app to not require the Play Store is a lot easier than switching payment provider backend.
Wero can fix the dependency on Google in a day, I don't think the dependency on Google is as bad as the broader dependency on Mastercard/Visa is.
That said, I'd much prefer a European implementation of the same remote attestation APIs that Google uses to convince payment processors that phones can be trusted to manage finances.
On iOS you don't really have a choice so until someone runs Linux on an iPhone, iPhone users are just screwed.