They are comparable in this case. Skyrim had hundreds if not thousands of quests. All hand crafted by devs. It would take more than that number of quests to level 7+ combat classes and 12+ crafting/gathering classes to 50, even if the exp gain was 1 level per quest. And in order for those quests to not be boring they would also need to be hand crafted by devs, else we just may as well keep leves.