these things are absolutely important but they are at most half of the picture.

intelligence is broadly heritable: https://www.nature.com/articles/mp201185

and a representative piece of a very large body of evidence that intelligence is the strongest predictor of achievement: https://www.sciencedirect.com/science/article/abs/pii/S01602...

Gladwell is making the case in his talk that Asians aren't better at math or are more intelligent. He speaks directly to your point: Westerners believe that you are born with math skills or you're not. Asians believe you can be good at anything if you work at it. Gladwell says it's because Asians had to work harder than Westerners to feed themselves, since rice is a very labor intensive crop. I'm not supporting or disputing Gladwell - I'm still pondering it.

I agree with you that intelligence is inheritable. I was thinking about the development of that intelligence.