For some projects the entire scope can fit inside a single head, but as the scope and complexity increase the work happens between the brains. This is where the issue lies. Collaboration is critical for most projects of any real significance. This is where offices are helpful. If you simply think about an individual’s work and not the team’s collective output, then offices don’t make sense.
I see a lot of people focusing on management in this thread, but in my experience collaboration is the responsibility of everyone. From an IC’s perspective, I found working at a remote company to be generally unpleasant. People would routinely engage in sandbagging, delays and it would be difficult to understand why things are blocked. I found that trust was lower, and people were far less collegial. This is true to some extent of remote teams as well, so I think there is just something in how the brain works that doesn’t click with taking orders from a television.
There are many instances where being at home heads down is much better for getting work done and strict rto mandates are generally unhelpful in these instances. But ultimately the conversations around this typically end up trying to talk past the point or gloss over the bigger issues which is that a healthy and productive team is what matters.