See I don't doubt that FaceID will be good. I don't doubt the quality Apple provides when they introduce features like this. I'm sure it will work amazingly well, because unlike almost all previous implementations Apple actually makes purposeful hardware for it.
The thing is, I don't want to look at my phone to unlock it. With a fingerprint reader - on my current Xperia and my current iPhone - my phone is unlocked before it faces me. I unlock it when I get it out of my pocket. I unlock it while lying on the table when it's facing the ceiling. I unlock it to peek at messages in meetings under the table. Needing to face your phone to unlock it seems to just be a really weird concession to me. As others point out, it also seems to be a minor concession security wise. It seems to be some typical form-over-function Apple thing again - UX and security concessions for a better looking phone. They should've slapped a fingerprint reader on the back once it turned out the under-the-screen fingerprint reader wasn't viable.
Having to go through some ritual to face your phone and slide it open to unlock feels like a hassle and a downgrade. Especially on a €1000+ phone. So yeah, the Apple distortion field is still a real thing it seems. Or maybe the way I use my phone is weird. But either way, I don't get it.