Current Pixel 4 owner here, and former Pixel 2 owner, and I very much miss the fingerprint sensor.
With a fingerprint sensor, the only time my phone would have any trouble unlocking would be if my finger was wet (trivial to fix and re-swipe). Face unlock fails all the time for all sorts of reasons, and is especially useless when I have a mask on (it's nice of Apple to detect masks and bring up the PIN pad without needing an extra swipe, but that's still a weak workaround). Even without a mask, I feel like the failure rate approaches 1% to 2%, which is way too much. For me to feel comfortable using it, I expect something on the order of 0.01%.
Actually I'm not even sure it's the failure rate that gets me. Even after using face unlock for the better part of a year, I still catch myself looking at the phone thinking it's waiting for my face when it isn't, and then I have to swipe up or hit the power button or something. Yes, maybe you can call these UX problems that can be fixed with software, but with a fingerprint sensor I know that when I touch it, my phone will vibrate, and I know immediately if it succeeded or failed.
I think also part of the difference is that Pixel phones have had their fingerprint sensor on the back instead of the front, like iPhones used to have. If the phone is just lying face-up on a table (and I don't want to pick it up), then having it on the front is much easier. But, in reality, I found that was rarely the case for me; usually it'd be in my pocket, or even if it was on a table, I'd want to pick it up anyway. The act of wrapping my hand around the phone would put a finger in roughly the right position to hit the sensor anyway, so it'd be unlocked and ready to use well before I was in a position to read anything off the screen anyway.
Frankly I just really don't like face unlock when compared to a fingerprint sensor.