This article is attempting to make some kind of statement about 996 and "look, now it's here!"
But this is plainly ridiculous. The Bay Area has been full of high achievers the entire time I've lived here (since the 20th century). All the startups I worked at, people would work Saturdays. Not all the time, of course, but it was quite common.
The article talks about how they are controlling for the variation across time, and they’re reporting a new signal. So even if everyone was working Saturdays before, everyone is more working Saturdays now. (Edited typos.)
But this is plainly ridiculous. The Bay Area has been full of high achievers the entire time I've lived here (since the 20th century). All the startups I worked at, people would work Saturdays. Not all the time, of course, but it was quite common.