Apple is giving verbal notices for not complying 3 days RTO, I heard on blind. Here, HR is forcing the attrition: either come 3 days to office or quit.
Everyone’s situation is different, but I know people at a big tech company you’ve heard of who are infamous for being, well, kind of assholes, who when given a similar offer by HR have said no I’m not coming to the office and no I’m not quitting and that has worked for over a year so far.
Of course that’s all predicated on your manager wanting to keep you and at least somewhat go to bat for you. Otherwise I expect it’ll lead to dismissal rather rapidly.
I know some people at amazon, which also has a long-standing RTO policy, that it effectively doesn't apply to engineers, since they were too important to risk attrition.
I don't know why anyone would voluntarily quit though: force them to make a scene and fire you for WFH. Best case you call their bluff, worst case you get severance.
Of course that’s all predicated on your manager wanting to keep you and at least somewhat go to bat for you. Otherwise I expect it’ll lead to dismissal rather rapidly.