I can get on board with that.
Face ID isn't always ideal, but I have an Apple Watch unlocking active as a fallback - if you pair both, the unlocking can actually feel seamless. Given you already have an Apple Watch.
I have that enabled and it is better for sure, but still not as good as my TouchID experience was but I then also find it will unlock the phone sometimes when I don't want it unlocked because of the watch. It's probably easier to summarize the issues I have with FaceID.
1. UI complexity - This is more the loss of the home button than just FaceID, but the fact that swiping up from the bottom replaces the home button there was the loss of 1 unique method of interacting with the phone. Apple used to have UI guidelines that would state to not try to use multiple functions with the same direction of a gesture, but because the home button took over the bottom up swipe, notification and control center are both from the top (granted it is clearly separated from right side for control center vs he rest of the top for Notifications, so this isn't too terrible, but I consider it a small step backwards in UI simplicity.
2. It's slower - I know, I know. Marketing tries to tell you it's faster, but TouchID could literally be unlocked
before my eyes even see the screen. It may have been slower in actuation, but the ability to trigger the authentication before you even see the screen to start using it makes the actual realistically usable speed slower on FaceID. I used to hit TouchID as I pulled it from my pocket and the first thing I saw when I looked at it was the Home screen ready to go. Can't get faster than that. FaceID needs my undivided attention to begin the process, even if only for a moment.
3. Authentication failures - This is where peoples experiences really come into play so I can't speak for others here, but in my experience it fails far far more often for me than TouchID ever did. With TouchID I maybe had to type my passcode once a week or less, With FaceID, I'm having to enter it at least every other day if not multiple times in a day sometimes for one reason or another.
4. Lack of Home Button to wake screen - This is tangentially related, but I never liked having the screen wake on a raise or a tap. I wanted to press the Home button to wake the screen. This ties into #3 a fair bit because now just touching the screen can wake it, I find my self accidentally opening the camera or turning on the flashlight far more often because just grabbing my phone makes the screen start paying attention to my touch inputs and in many cases... trying to authenticate FaceID and failing repeatedly because I'm not trying to interact with my phone, and this then leads to having to type in my passcode the next time I want to use it because of too many failed authentications. Now, I know the lock button can be used to wake the screen works, but home button was just easier to use that way for me, so even having to use the lock button only still makes the usage just a little more uncomfortable. I do have raise to wake disabled which helps avoid the nuisance screen wakes some.
5. Swiping confusion in the OS - I'm not really sure how to quantify this, but there have been times where I'm just trying to unlock my phone and get to the home screen and it literally takes swiping up several times to get it to register. I don't really understand what the situation is that causes it, but I think it might be getting confused and thinking I swiped right first because my swipe wasn't perfectly vertical and the software locking onto that action instead of the unlock swipe I really want. But this kind of ties in a bit to #1 because the loss of one input method and subsequent merging of the remaining options makes each more complicated to use.
Those are the main things for me at least. None of them are absolutely terrible, but each just contributes a little but to a worse experience for me. I would happily take the return of the chin if it meant a home button with TouchID could return. But in fairness, the ease of use of the OS even on TouchID phones got more complex and annoying after FaceID was introduced too because of the multiple ways of doing things.
Side note, I'm also in the camp that wants 3D Touch back and the headphone jack back too, but we all know those will never happen. Aside from Battery life and camera quality, iPhone 6S was peak iPhone. (5S design was my favorite though). Anyways, sorry for the long post, but this is my opinion on why TouchID was better. Also, the TouchID security was good enough for the purpose it serves, whether FaceID is technically better or not doesn't matter to me at all.
