I think partly because Google and Apple controlled the contactless bits of the phones for many years, the non-OS-makers like WeChat and AliPay made use of the open technology of QR codes. I think theoretically you could build equivalent things as they have with NFC today on those platforms but on the other hand being able to set up a “POS” with nothing more than a printer does have an appeal to it, even if writable nfc stickers cost 5 cents you still have to go buy some.
I think there is also something about how easy it is for a business to adopt a QR code by just needing to print one out instead of having to go out and buy a whole payment terminal.
In Russia they tried to use bluetooth after being sanctioned from using NFC.