They are used to sitting at home and working maybe 30 minutes a day and getting paid for 8 hours.
I don’t like working from home. The fridge is there.
If you spent the two years prior to covid sitting in an office working maybe 30 minutes a day and then trying to look busy for the other seven and a half hours, hating the commute, the office politics, and the lack of flexibility, doing it from home for two years is certainly a big thing to give up. Of course, some people in those jobs are about thirty minutes of real work per day away from having nothing to do and no reason to draw a paycheck (and their managers are necessarily in the same boat if their job is to supervise those thirty minutes worth of work).
The nature of business is changing, has changed, and it's not going back to what it was like in 2019... nor should it. Some industries will see all the corporate office space they don't actually need and cut it to save money. Some industries will see all the excess employees they're paying and cut them to save money. Some employers will realize that remote work means they don't have to pay local wage rates to attract candidates and the offshoring of the late 1990's is going to start back up again. The people living inside that silicon valley tech bubble are going to be hit hard.
As opposed to driving in to the office and working maybe 30 minutes a day and getting paid for 8 hours? If you can't tell whether the productivity has dropped for those working from home as opposed to those in the office then you're a pretty bad manager. If the work is getting done where does it matter where it's getting done?