I’ve used both and I prefer NFC over UPI. I just need credit card and phone that supports NFC. No need of phone number, deal with entering pin, scanning QR code, linking account during setup, etc. Biggest plus point with linking credit card is fraud protection.

In US NFC is best and seamless since most people have high end phones. In India maybe UPI with QR code is better solution since you only need phone with a camera.