Here's what we know about Face ID:
If I am using my iPhone X as a GPS on a vacation and I've got it in a vent mount and it's pointing directly at the back seat which vent mounts tend to do, I have to remove it from the mount and point it at my face to unlock it. That's not good.
If I am using my iPhone X for Apple Pay at Starbucks and today all I have to do is lie it down on the terminal, lightly apply a thumb print, and I'm done....with the X I'm going to have to hit a button, hold the phone to my face, then lie it down on the terminal. That's really not good.
If I am awoken at 3AM and can't get back to sleep and need to do some light reading in bed in the pitch darkness on my iPhone X, I'm going to have to pray that the thousand points of light will work on my puffed and scrunched bed face lying on the pillow or get ready to hit a bunch of buttons. That's really not good.
If I am in a meeting and have my iPhone X face-up on a boardroom table so I can glance at alerts, if I get a text message and want to open it unobtrusively so as to not insult the person who is talking, instead of sliding the alerty and depressing a sly finger I have to raise the phone, point it at my face, then place it down, and then navigate to the message. That's really not good.
Those aren't 'insinuations'. Those are facts. And there are plenty more use cases where Face ID is the killer feature of the iPhone X. "Kill" as in, it kills it for me.