The pro-RTO don't talk about why is outsourcing perfectly ok but not WFH? All large companies have people outside of US, WITCH (Wipro, Infy, TCS, CTS, HCL) in India and some have people in Europe, South America, etc.

Second, even in large campuses (HQ of the company), many buildings, most people can't find a conference room to meet (they are almost always booked), and lot of them just webex from their desk because meetings are back to back, you won't have the 5 minutes it takes to walk to the conference room in the next building. Rarely do people work with just a few people around them. People work with others in different buildings, locations, countries, timezones. When this is ok, WFH is perfectly ok.