Removing/Nerfing Onyx Apples-How would it effect the game?

It would cause inflation on prices of zakum helmets and horntail necklaces/eggs, along with inflation of the equipments and skillbooks those bosses drop.

not inflation just raised prices, inflation is when the value of currency as a WHOLE is lowered. I.e Less buying power, it will slowly drift to higher prices for other zak and ht related items but thats about it.