Just gonna say it again.
Does a master swordsman know how to make a blade? No, he'll tell the smith his opinion of the weapon and any improvements he'd like to see. Then the smith would get to work making said improvements. The swordsman only knows what he wants, he doesn't know how to get from A to B.
Its the same with magic.
Maybe. Maybe not.
First, lets assume you are the greatest mage ever. No one makes spells for you because no one can cast spells like you. You would then learn to create your own out of necessity.
Second, enchanting is the act of endowing an item with a magical effect. Thats not the same as spell making.
While I do like your idea that its still in they just changed how, and its under a skill now, with the information we are being given, which could be false, we are left to assume it isn't in at all.