Facial Unlock+Under display fingerprint sensor will be standard on Android.
I see Android phones adopting fingerprint sensors under the display, not necessarily because it's the better option, but because they will need something to sufficiently differentiate their products from the iPhone, and Face ID is simply not a feasible option at this point.
Before you compare Face ID with facial unlock, do also note that Face ID is essentially a miniaturised Kinect in your iPhone, which has ramifications for additional features down the road besides unlocking your phone.
No changing the meaning means changing the meaning.
I said the best solution is to have 2 fingerprint sensors(one on the front, the other on the back) plus facial unlock and your answer to that was: sometimes less is more.
Imagine an iphone x that had all those 3(and they would all work like anybody would expect).
How would just having facial unlock be faster, or better or "less is more"?
Because it sounds needlessly redundant and excessive?
Let's run through the various permutations to be had from an iPhone hypothetically sporting Face ID and 2 Touch-ID sensors.
Scenario 1: User uses only Face ID and disables Touch ID. Why even bother with Touch ID then in this scenario? I would just be paying extra at no benefit to myself.
Scenario 2: User uses only Touch ID and disables Face ID. If we take Apple's word that Face ID is more secure than Touch ID, then including this option would actually weaken the security of the device for this subset of users, because they are not using the more secure option.
Scenario 3: User uses both Face ID and Touch ID. I guess it could make for better security, but again, I believe that part of the purpose of adopting Face ID is so that you don't even have to think about unlocking your device. Simply look at it and it's unlocked (which works wonders with that feature which auto-hides notification previews on your lock screen). It's an extra layer of interaction that gets removed, which in turn makes your device more personal to interact with.
So "less is more" in this context. For one, the user doesn't need to make a "pros vs cons" decision flowchart as to whether to use Face ID or Touch ID or both. If it's the 8 or 8+, use Touch ID, and if you have the iphone X, then just use Face ID, because those are the only options available.
Second, sticking solely with one form of authentication (Face ID here) results in the greatest good for the greatest number of users.
If you ask me, I don't need 4-5 different ways of unlocking my device like what Android offers. Just give me one optimised solution and I am good to go.