I'm not sure it matters what part is due to fundamental dynamics. The goal should be to add a feedback loop from the top to lower levels so as to improve mobility dynamics, which encourages the view that hard work and ingenuity pays off with decent probability.
Well, fundamental dynamics are likely harder to counteract than some of the human factors which may be a bit more arbitrary and anachronistic. Not that this is a show stopper, just something to keep in mind.
I think something like universal basic income might be an example. This gives people a little more security to improve their education or be entrepreneurial. Ultimately, this ought to give them improved probability of upward mobility with less risk of downward mobility.
