According to this:
https://support.google.com/googlepay/answer/14555219?hl=en
Google Pay is no longer available in the US. I can't find anything about non-US use.
But, security-wise, Google Pay/Wallet is supposed to be more secure than credit cards because:
" Google Pay purchases are tokenized, which means that the service sends your credit information using a unique code for each purchase. If the information could be intercepted, it would not be useful to a thief or hacker, because your credit card information isn't present.
Perhaps even more important, though, is the physical security that Google Pay offers. If your actual credit card is lost or stolen, it can potentially be used to make purchases, at least until you notify the credit company and cancel the card. But when using Google Pay on your phone, your credit card information is protected behind a passcode or biometrics like facial recognition. "
That's from :
https://www.businessinsider.com/google-pay
I don't know when that article was written and that's not exactly a security research article, but it seems reasonable.