it more a economic thing , customer need to pay extra for roasted wood need some justification .
for the darker look , this point not really apply to Mahogany as it already quite dark .
for stability and tone wood part ( I find this point true on Ash and I willing to pay extra ) , I think many people has try mahogany but maybe not so obviously.
there some roasted Mahogany neck in the market, but much less than maple .