80% of them are FOSI just read a survey on Reddit that something like 80% of tech people said they'd quit if made to go back full time. I'm sure if Apple went full time, there's spots for a lot of these people at other tech companies.
Silicon Valley pay scale is going to drop dramatically once they no longer have to pay enough to allow average devs to afford a mortgage on a $1.4M 3br/2ba ranch 30 mins away from office.