They just always seemed like different unrelated attributes to me. min/max/restore versus visible = true/false. I imagine people manage the x y coordinates and min/max/restore (restore = regular) states of their windows, while independently managing the window's visibility based on channel activity or other criteria. The change you propose would force a hidden window to become visible if it's merely repositioned.
I use channel visibility based on channel activity, but since my channels are always max/min, and never regular, I don't have a bone in the fight. Other people who use tiled or cascaded windows might.
31./window -a now shows a window that was hidden with /window -h.
If you use /window -a, it will behave as if you used both -w and -r