I've come to the early conclusion that I prefer Touch ID to Face ID. I might even prefer it by a lot. Granted, a year from now it might not be a big deal any more. And that particular issue will not be relevant to someone coming from a X or later: you're already used to it! But that's the one thing I miss, is Touch ID:
--Waking up the phone in the dark, it's simple to figure out the correct orientation. This will not be fixed by an under-screen fingerprint reader.
--Getting to the home screen from sleep requires one not-that-precise physical motion (rest thumb on Touch ID sensor, wait a quarter of a second). Face ID requires two (point phone at face, and swipe up), and the swipe requires some precision. This will also not be helped much by an under-screen print reader. I cannot just feel for the button.
--Apple Pay was much easier. I'm already holding the phone in an orientation where I can rest on the home button. Take phone out of pocket, hold near reader, rest thumb where it already is. On Face ID, it's take phone out of pocket, double-press the side button, possibly point phone at face, hold near reader.
That last one feels like the most "just get used to it." My instinct is to take out the phone and make a direct line to the reader. My instinct needs to be to take out the phone and hold it normally first, as I double-press. It's still more work.
I'm not considering the mask issue. I do own an Apple Watch, and generally it does a great job at auto-unlocking the phone for me when I have a mask on. BUT it does not (and should not) do so in an Apple Pay situation. There I MUST enter in my (11-digit) code. Now more often I just use the Watch itself, which I was doing sometimes anyway. But sometimes it's just easier to whip out the phone.
This area is the ONE THING that I really feel I've taken a step back with the 13 mini. Otherwise I am a very satisfied customer!