If we assume that it's illegitimate for someone to prosper that much behind growth and optimism that growth will continue (ie he didn't sell his stock), then the legitimacy of the net worth of every single direct or indirect (eg via ETFs) investor in Amazon, every single indirect beneficiary of investments in Amazon (eg recipients of pensions whose funds hold Amazon), and every single employee with an equity stake needs to also be questioned.
Sure there are some differences here such as stock options, but even if we divided Bezos's net worth by 2 or 3 to account for this I don't think it would make much of a difference.
My only point is when you're talking about his growth in wealth, you're always de facto talking about his stock holdings and their growth and the idea of objective compensation goes out the window. In fact, even if you're talking about straight compensation, it still is part of the discussion because clearly in this case, he is willing to take a paltry salary because he is benefiting from massive stock value growth.
As for this point:
>If we assume that Amazon is fairly valued and that Jeff Bezos's holdings of Amazon are in line with his contributions
He is not being 'compensated' via stock nor is the total amount of stock he holds fluctuating based some sort of objective analysis of his contribution. He could contribute nothing and retire and still hold the same amount. So I don't know how you can assume that.