In other words, about a hundred times a day my train of thought is interrupted for a second or two while I stare at my phone and wonder if FaceID is going to work. This is a pretty terrible pattern of disruption. Technology should disappear into the background instead of inserting itself into the foreground of my attention every time I use it. The fingerprint home button was more reliable, and it was much easier to anticipate when it was going to fail because of a wet or dirty thumb.
FaceID fails when your face is not fully visible.
That would be nice and simple if it were true, but it's not. Sometimes it fails when my face is fully visible. Sometimes it works when my face is not fully visible. It can work or not work with the same pair of sunglasses depending on... who knows? Maybe I'm just not smart enough to figure out the exact meaning of "fully visible."
Also when it fails with sunglasses, and ask for password the first time, immediately logging in with passport will make subsequent unlocks with sunglasses work better (presumably it marks that face adaptation as "correct").
Even the next Pixel4 is moving to using FaceID, going back to a home button or fingerprint scanner would be a step backwards.