I did, the agent tried to tell me that I had to use the facial recognition system. I pointed at the clear sign which said it was optional. She called a supervisor and they checked my ID as normal.

I fly often for work and have only seen this once out in the wild.

Besides having to insist that it was optional, there was no additional screening necessary.

Customs office in Seattle just pointed a camera at me and said “Ok you’re good.” Didn’t even ask for my passport.

Not sure if this is the same program, but that experience was quite jarring.