For some reason this (along with piannucci's explaination) really helped it click for me - while the gas has a very high blackbody spectrum temperature, emittin

For some reason this (along with piannucci's explaination) really helped it click for me - while the gas has a very high blackbody spectrum temperature, emitting hard radiation when it's particles collide at high speed, it effectively has very little surface area from which to emit that blackbody radiation.