Anecdotally, I'm at a larger multinational corporation and our site has been mandating a new RTO policy and have not been granting exceptions based solely on seniority. In my personal opinion I believe it's mostly a soft layoff, so they can approve exceptions on a case-by-case basis.
Indeed. Apart from really aggressive, "love the bad press" type of employers most would try to appear reasonable from outside while largely rejecting wfh/remote requests lasting more than few months.