That's not how it works, the people still have the power of the Nephalem but they are just not aware of it and they can't learn how to use it without exterior help because of the effects the Worldstone had on them.
How do you know that's not how it works? The Nephalem were immensely powerful so why could humanity not lose its power after generations of interbreeding where as the heroes clans all seem to stay semi close to one another. Barbarians mostly stick with barbarians as mates, Necros as Necros, etc etc.
Think of the powers for a second not as powers given from early generation Nephalem but as culture between each "race" of people in sanctuary. Just like in the real world as we interbreed with one another we become more of a single race of humanity rather than diverse cultures because we adopt common ones and more and more abandon older ones.
A lot of my ancestors on both of my parents sides were German but we don't celebrate Oktoberfest or run around in lederhosen.
I know it's kind of hard to translate it from culture to powers but that's the way I've always imagined it worked. The more the weaker human populous breeds with other weaker humans the power becomes diluted.
Anyway I hope you understand what I'm talking about and if you have any proof of another way it works feel free to type it here and cite sources if you wish.
Quote from "Shadowdragon85" »
The humans are nephalems but just think of them as watered down versions.
At some point all progenitor cultures in the US became sub cultures and much different culture arose.
I always assumed that the different groups in Sanctuary got their mana from a force that does not exist in reality, like the Nephalem and their supposed powers are simply amplifiers and magic is something all things are predisposed to. So lets say the World Stone affects the Nephalems children, who is to say that the quantity of the effect is universal. Suppose for a moment that the Paladins of Zakarum were as powerful as they were because they were furthest from the effects of the stone. Like the effect weakens with distance in furocity. It makes sense, the Barbarians are hardly magical, they're pointblank with the stone, and yet the Sorceresses and Paladins are so heavily magical and they're also far away.
Then the Rogues, who are at the medium point, they don't really use magic but they have a little capability.
The only contradiction I can think of are the Necromancers and I don't really know where they center at. It just seems that the closer they are to the stone, the more alternative their capability becomes