It amazes me that people think United or any other airline would purposely torture its customers by keeping the seatbelt light on when they know it's safe. In my most recent flight, I and several other passengers did get up after a prolonged period of the seatbelt light being on in order to use the lavatory. I don't blame anyone for doing so but we are making a conscious choice taking risks of turbulence versus an accident in the seat.

Whether it's FAs providing service or a handful of passengers trying to get to the lavatory, everyone on board is certainly at less risk of injury from predicted turbulence than if a majority of the passengers unbuckled for convenience and comfort.

I presume the pilots are using their professional judgment on when the turn that light on/off, FAs are using their professional judgment on whether to be up out of their seats despite a seatbelt light being on, and most passengers have NO professional judgment when it comes ot aviation operations (I certainly don't claim to have any).