In a 2 stroke engine, hotter is not better, lean running is also not better for the same reason. Unburned fuel in the cyl head is also a cooling process. It maintains the combustion chamber temp at a certain degree. Leaned out cyl's will cause detonation/pre-ignition and the piston to come apart.
The misconception of hot plugs in two strokes has nothing to do with the spark. It's in the insulator and how quickly it can conduct cyl head temp to the water jacket through the plug wall for the circulated water to carry the heat away.
A perfect example of this is in those engines with a surface gap plugs, no electrode sticking up, just a small dot in the center of the insulator. They were engineered for hot running engines. The insulator is right at the surface of the plug.
This is not theory, but facts, as I learned them from Champion spark plugs. If you want to test out these facts for yourself, get two plugs for the same application, One hotter than the other, and compare the two. See where the insulator contacts the plug wall.