My impression is that the main reason most people have so many meetings is because meetings are equated to work. If you are in a meeting, you are at work and you need to work. This is because, in a meeting, everyone is looking at everyone else with the expectation that they are working. But if you are not in a meeting, this expectation doesn't exist, so you are basically not at work and you don't need to work.

In particular, thinking only occurs during meetings. And if it didn't happen during a meeting, it didn't happen.

Call me cynical, but it explains immediately why the vast majority of companies don't tolerate remote work unless they're forced to by a pandemic. Office work means someone could be watching you outside meetings, which causes some work to happen outside of meetings and raises productivity.