I tried ask around this question as well, seems like no proper answer.

My thoughts is :-
If paint first :-
-during installation and moving in other big stuff might scratch the wall
-easier to paint because empty wall and house fixtures and less thing to mess up.

Paint after everything done :-
- During painting might drip/spill paint on other fixtures
- Paint will only cover empty wall, means if u do color next time if u happen to replace cabinet or different design light or sort, that wall behind will be with old paint color, and if u happen to plan to change color will be even harder to even the color that is inconsistent.

Would like to see how others look at this as well.