As a manager with 10-15 reports at a company you've probably heard of, I think the main question is how much they will need to contribute. I put up a PR or three a week, usually in non-critical path flows or system support, and its honestly fine. I could barely contribute to the productivity level of even one of my junior engineers, but I can debug production issues and ship code AND be a good manager (with a decent work life balance).

I feel like managers should be able to contribute. Managing a good team isn't that hard, though managing a bad team (or a good team in the midst of a ton of bad processes) is a nightmare.