Early on in my career, I didn't think of working space requirements as applying to anything but the main panel.
As I've advanced, I've come to think of them as applying to literally everything.
First paragraph in 110.26 says, "...working space shall be provided and maintained about
all electrical equipment..."
However, Handbook notes say "Minimum working clearances are not required if the equipment is not likely to require examination, adjustment, servicing, or maintenance while energized."
Where my "the Handbook notes aren't code" people at? lol.
I think
@infinity makes a valid point that there are some instances where you could challenge the real world applicability of the code, but at the same time, it says what it says.
I think you should strive to meet working space requirements for any and every piece of electrical equipment, especially after you've experienced the frustration in the field of having to work with a less than perfectly accessible piece of equipment. However, I feel like, if we're going to be honest, there are going to be a few instances in which it may be slightly less than perfect and that's a judgement call for you to make.