How's touch ID a step back?
Doesn't work when your hands are wet.
Doesn't work when your hands are cold because they're all pruned and wrinkly.
Doesn't work when you're sweaty (see the first point).
Doesn't work when you're wearing gloves.
Doesn't work if you get a cut on your finger (been there, done that. Luckily I'd registered extra fingers).
I found TouchID to be far, far less reliable than FaceID.
paying in the world of masked society
With an Apple Watch, FaceID works perfectly with a mask on for both unlocking and also for using Apple Pay.
I've never had any problems with FaceID. It works if I'm wearing a mask, it works if I'm wearing sunglasses, it works if I'm wearing a hat. It works if I'm wearing a hat and sunglasses. It worked when I grew a huge beard and then it worked the day I shaved it off. It worked when my face was skinny, it carried on working while I got fat.
It works when I let my hair grow really long and it carried on working when I had a haircut.
It's just far more reliable than TouchID ever was.
I honestly didn't expect it when I changed from TouchID to FaceID but I'd never want to go back.