There's really not debate about anything. Each has it's own properties, and some people are intolerant or allergic to PG.
Allergies to PG are pretty rare but intolerance to high levels is not so rare. Personally, I have problems with vaping juice with more than about 30% PG.
Allergies or intolerance to VG is extremely rare. But VG has its own drawbacks.
VG mutes flavors. It's sweeter and thicker than PG. It fouls cartos and attys faster than PG. It lowers the throat hit of nicotine, which leads some people to believe that throat hit comes from PG, which is incorrect. VG produces more vapor than PG.
PG is thinner and a better flavor carrier. It doesn't mute or dull the flavor or throat hit like VG does. It doesn't produce as much vapor as VG, all else being equal. PG doesn't cling to coils as well as VG, so it tends to leak more if you're dripping.
For maximum flavor and throat hit, use more PG.
For maximum vapor, or if you have an intolerance to PG, use more VG.
It's a balancing act, so most people use a blend.
