When you got major companies like Twitter, google, Facebook, and others already saying WFH is a permanent option that’s put pressure on others to figure out how to make it work.
Talent is needed at many, many companies and if the talent is a.) needed and b.) good enough the company will make “exceptions” to the rule.
Enough companies make enough exceptions and it’s a mainstay policy.
Overall, the other part is that companies that now offer remote work as a permanent option may not have to pay SF salaries so that’s a bonus to the company. It’ll go both ways, the company can say I’m not requiring you to live in high COL area and we have an office in X city, we pay 10% above the market average of ~35-40 cities so they’re still competitive on pay (assumption being that most companies move to this model, FAANG may overpay still but that’s always been the case) so now what do you do?