I've seen variations of this play out time and time again. Whether it's upper management asking their employees to track how many hours their work actually takes, with the secret intention of making them prove they don't need to be paid as much because their work takes way fewer hours than the original contract said; or bosses favouring employees who look overworked over those who actually perform well.
If I had to pick my battles, I would definitely pick this one, but I would approach it not with feelings or emotions, but with receipts. Maybe this employee could send a report of his team's productivity with a message explaining that they perform that well because they approach their work by trying to reduce stress. Stress is minimized by focusing on tasks instead of schedules and rewarding results, not performative panic. As I'm writing this, I realize it might be a lost cause, but we're all free to choose the hill we stop our journey on.
If they don't understand it this way, they might have to learn it the hard way and lose their most objectively valuable workers to keep the ones who only look valuable, but that's honestly a loss for everyone involved.
I honestly think there is a way to approach this issue so the executives understand what's happening, but it would definitely take excellent communication skills and dedication.
They are the only ones who know if they're that interested in the company to invest all that energy into it.
They have another option: to act as if they were incredibly stressed while doing the same thing they were doing before. Maybe that's the way management wants them to go.