I remember the fad. I was around for the Extreme Programming era. But, I've never worked anywhere that pair programming was the norm, nor have I known any developers that wanted to pair program, in the general case.
My personal experience is, of course, not representative of an entire industry, but I just have a hard time imagining it being a common thing. I like working with other people and helping juniors sort out their problems, but I'd quit my job if I had to take turns writing code while someone else watched and just sitting and watching someone else writing code. Both of those things seem horrible, to me.
I love pairing. It always results it better outcomes than not pairing and I've been saddened by the slow decay of the term to now refer to like "talk to me a bit until I'm unstuck" instead of "both work together and get it done"
I worked at Pivotal Labs, it was an amazing experience to be in an environment where everyone was onboard with a very well defined methodology. Certainly not for everyone, but everyone who was there had the same mentality. A bit like you'd expect from a cult or the military.
I consulted on an internal project where the leads literally made one dev control the keyboard and another dev control the mouse! It was the most ridiculous thing I ever saw. I fought for those poor kids, the leads were eventually fired or quit.