I have some strong opinions about this.
Earlier in my career (as in, first two-three years out of college) what was needed by my employers were CAD files. If there’s a better way to pump CAD than headphones, stimulant of your choice, and a good chair/desk/mouse/work environment, I’d like to hear it. That is what was required. I would have to go to our then-tiny model shop and cut foam sometimes.
Fast forward ten years or so, and the ten-year-older-Slippyfish was seeing a physical therapist to help recover from some injuries. PT suggested getting up, walking around more often, to simply get flexibility and mobility. The odd part was that once I followed the PT’s guidance, my overall ‘productivity’ actually increased - I was talking to and engaging with other people, seeing what was going on in the model shop, having chance encounters by the water coolers, etc.
I and my team now have standing desks (except for the intern). They are height-adjustable with a hand crank. Most of the team tends to spend a week or two with them up, and then crank it down, and stay there for a couple weeks. I’ve found if I need to pump some intense CAD that sitting tends to work better for that kind of concentration. Standing desks encourage walking around - no surprise there. But especially for the more senior people on the team, I think they need to realize that the body language and persona conveyed by sitting all day at your desk with your headphones on - “being productive” - is going to be a hindrance in getting where they want or need to go with their career, unless their career goal is CAD modeling/rendering superstar, full stop.
TL;DR - if you treat it like a ‘desk job’ that’s what it will end up being for you.