COVID was a big, big change to work policies. But still, you have to look at “hybrid” work in the context of the history of changes to the workplace. When the labor market gets hot, companies look for ways to give employees benefits, especially non-salary benefits. 40 years ago, it was “flex time”, some places let you leave early on Friday in the summer. Some places tried a 4 day week. Today, with the advance of technology, its hybrid work. Once the labor market crashes and unemployment goes back up, most of these hybrid work policies will be eliminated or cut back significantly. No question. The only people who will remain hybrid will be people who are more efficient in the field, like technicians and sales people.
I think it is a mistake to assume that labor-management dynamics will be driving the in-office vs. work-from-home business model. Ultimately, this will be determined by competitive forces related to overhead costs. Companies in industries that can operate successfully with limited office space by having staff work from home will simply run their competitors who insist on leasing expensive office space out of business.