The movement was the expensive part. Audemars, Vacheron and Patek only made movements. The retailer would then put it in a case. That’s the entire point of PG’s essay.
> if you couldn't tell them apart, they wouldn't be any good at signaling, the entire point of wearing them
Which might lead you to revise your hypothesis around why these watches were bought and made in the “golden age of watches.” Then as now there is such a thing as quiet luxury.
I don't think thats really true, Audemars & Patek deffo made entire watches in the 50s.
Don't get me wrong they also designed movements, but by the time of the quartz crisis, Patek bought in movements from outside.
It doesn't really help that omega and tissolt were merged with Certina, ETA, hamilton when then turned into swatch, which basically dominates the entire swiss watch industry along with rolex and richemont(who own Vacheron)
The watch manufacturer, as part of their reputation, buys “premium” internal components. And then the hardcore watch-heads get to know that this model has that premium movement. Everybody in the club gets to signal to each other by knowing internal details that outsiders don’t notice (or even details that can’t be noticed, I mean, I assume by nowadays non-premium-brand movements are functionally identical to the premium ones).