Cessna thinks a spin is an aerobatic maneuver as does pretty much everybody else involved in aerobatics, including regulatory authorities, competitions, and airshow acts.
Yes, I agree with you on that Big Pistons...
I suppose with my broadened perspective, I would like to include spiral dives in my "aerobatic" category too for this purpose. Thus, I think that PPL's should receive basic training in specific limited aerobatics (spins and spiral dives)!