Pretty much all my coworkers also reckon they are much less productive in the office.
If your job is not face-to-face with a client/customer, then the only thing you are "serious" about at the office is socializing. That is great if you work with all your friends. If not, you and everyone else there is wasting time. It is simple to have meetings, get instant feedback, ask questions, share data, call, anything really from remote. At one time that was not true, but in 2023 people that are demanding office time are either trying to justify the cost of an office or are micromanagers with some sort of complex.
Come on, office attendance is not a sign of being "serious about their work."
Farting in an office chair all day is frequently a performance to feel busy or fill other needs in their lives.