Medical work and software development are very different kinds of work with very different difficulties.

A lot of medical shift work is about being there, not necessarily about doing stuff all the time. There's a lot of standby-duty. It's sometimes physical work, sometimes emotional/social work, sometimes actual brain work (researching stuff). It's quite a lot of different types of tasks over a shift.

Software develompent is highly-concentrated brain work without meaningful built-in breaks. You spend all day staring at a screen, doing high-level logic non-stop. Humans aren't built for that kind of work at all, so it's really difficult to do that for extended periods.