NFC is used across multiple apps, if you don't need it for a specific amount of time you can create a routine to turn it off completely. Currently theres no way to turn it off for individual apps through routine.
You don't even need to keep NFC on. If an app uses NFC (like Samsung Wallet), it turns on automatically and then shuts off when not in use. Except for Google Wallet. If you use Google Wallet, you have to turn the NFC on to pay and then turn it off when you are done (not sure if it turns off automatically after a period of time as NFC is not meant to be on when not in use).
I can't speak to that, only my own experience. I have never manually turned my NFC on or off on my phone or watch. When I use Samsung pay on my watch or phone, the NFC goes on automatically (I guess, 'cause the payment goes through), and the turns off at some point. When I chance to look in my quick panel, the NFC is always off. The only time I am asked to turn NFC on is when I use Google Wallet, so I don't use it.
I have an A54, previously had an S10 Lite with a watch 4. I have not had to turn NFC on or off with any of them.
