More likely that the companies that institute this will hemorrhage talent that is offered a better deal by competitors. 996 works because the supply of Engineers is quite high in China.
Won't work when the market colludes. And Silicon Valley Big Tech already got caught in such a cartel - see [1], debated back then in [2].
[1] https://www.latimes.com/business/technology/la-fi-tn-tech-jo...