It is a matter of efficency. If you are painting x amount of material will it be faster and easier to run the brush and roller vs all the prep work involved to spray. Occupied interior dwelling with furnishings i say brush and roll.
Exterior or new unoccupied area spray it.
I do a lot of new stuff and spray trim and ceiling and closets. I cut in and roll walls.
If i am doing a interior repaint it is 99% quicker to use the brush.
Exterior i like to spray what ever i can.
For exteriors, it's almost never advisable to spray, unless it's a stucco, textured, or otherwise difficult hand application
(granted the houses in your areas could be way different than in mine)
Awww. Thats old school way of thinking. These days lots of exterior work gets sprayed.
It is not always the best method. lots of factors to consider, overspray, efficency, material, prep, ect ect. Yet when the conditions are right, man talk about a time saver. 60% of the time though the factors do not line up and it is brush work.