Nobody said it was an Apple exclusive.
But to be fair, after trying to do payments in various other ways, Google eventually built their Android payments platform to be an almost perfect 1:1 recreation of Apple Pay.
(And this is a recurring theme with Android. I'm not saying Google aren't within their rights to build things however they wish, but it is remarkable how often Google make loud smug noises about how they've done things differently to Apple—only for those points of differentiation to quietly disappear a few years later. Say what you will about Apple, a company that makes plenty of horrible mistakes, but it's remarkable how often they do get things exactly right the first time.)