WFH vs In Office
First point is some jobs require one to go into the office, others can be done remotely, and some require a mix of time wfh and in office. Also lets define WFH as a situation were a person might darken the office no more than once or twice a quarter whether scheduled or not. Lab work (I am an ex lab rat) will require going into the office. Some drafting work might require going into the office (the equipment required to make drawings might be rather awkward to set up in a home. Sales, marketing, can often be done from home. Many IT jobs again can be done from home, though some will require someone babysit the servers, etc.
Also, as czechitout noted many meetings have to be on Zoom/Teams/etc. because not everyone is in the same state or country even. So it does not matter if one joins the meeting from home or in the office (home might often be easier).
Once the pandemic eases and some sort of normality is restored I do not see many companies going back to having the staff come into the office with the same frequency as prepandemic. My group and others, because another group required more space, lost our individual cubes and as of yet my group does not have any cubes to call home.