In my limited experience, it is because nontechnical managers are incapable of evaluating our work. Since they can also not ever admit to not knowing anything,

In my limited experience, it is because nontechnical managers are incapable of evaluating our work. Since they can also not ever admit to not knowing anything, they rely on a crude metric like physical presence or time served. Then, they can pretend to be managing you by suggesting buzzwords they saw on linkedin.