The guy was in one of those "non black cab" Taxi's, presumably quick whited enough to enable rear child locking.
Fair enough, that changes things, the child lock scenario didn’t occur to me, I just had to ask my wife if her car, (3.5 y.o.) had child locks.
She replied, “Of course it has silly ********, as did the previous 3 that you bought for me brand new!
I had no idea, I’ve never activated a child lock in my life, both my kids were adult and married when my wife and I got married, she had none from her first marriage, and we’d agreed to have none ourselves.
If I picked up any of my grandkids in my Black Cab, the doors locked automatically as I moved off, and I never picked them up in my wife’s car, once I got out of the Black Cab I never looked at another steering wheel.