I think it's important to remember that we're not utterly helpless about this matter. It is true, of course, that some of our native intelligence is determined by our genetic make up. However, there is also that kind of "stupidity" that is another word for the mind poison of "ignorance" or "delusion". We can certainly train ourselves to become less stupid in this respect by diligently reminding ourselves to notice, to be aware. Yes, life is difficult. It can be a little less difficult if we are careful to pay attention.
Life is hard, but it's harder if you're stupid.