I used both, and in my experience, it looks an order of magnitude more polished than Face ID.
My ultrasonic sensor on my Galaxy S10 is absolute garbage compared to Face ID on iPhones. It works 1/3 of the time and it's slow.
Realistically ultrasonic is the technology Apple would go with, considering how lighting up a patch of screen is just... Ugly.
There's another problem: FP sensors don't cover the entire display. There's a huge learning curve -- getting used to where that small patch of screen is -- and even today, months after getting my new device, I miss often.
We're only now having issues with FaceID because we're wearing masks all the time. It's intuitive and it "just works".
There are also many new phones with very large sensors that basically cover most of the bottom half of the screen.
Personally I still think a rear or power button based sensor is superior to under the screen, but hey progress is progress.
I'm drinking my coffee skimming through morning news. I get distracted, phone locks up. Now, on Moto Z I need to just touch it and it works again. On iPhone, no, it won't unlock at all while it is lying on the table.
On learning curve: you exaggerate the hugeness of the learning curve. When I upgraded my Moto Z play for Moto Z4, I learned... Well, maybe in 30 seconds during device calibration. Now, I've had some experience with side button fingerprint sensor on Moto Z3, and it was the reason I decided to skip upgrade that year. You see, the phone always moves when you try to unlock it, unless it is secured somehow to stay in place (by your other hand or by assuming some pose where it doesn't move)
(Can't say anything about Samsung, I'm boycotting this manufacturer since 2010)