Even setting aside the ethical and legal implications of this conduct, it really underscores a key fact about Trump that right-wingers never really got: he was a singularly incompetent business man. When you look at how his net worth moved over time, it was already clear that the return he was getting on his money was far below what any moron with a passively managed index fund would have gotten in the same era. And once you consider that was despite getting these regular infusions of additional wealth from his father, over time (including a large inheritance), it becomes clear his investment return was just a small fraction of the average market return. You literally could have blindly thrown darts at a list of stocks every year and outperformed Trump's business empire by a very large margin. He was utterly inept. After his father died and he could not longer rely on these repeated infusions of unearned wealth, he tried to make up for it by relying more and more on outright scams, like Trump University, to try to avoid additional bankruptcies. When even those began to dry up, as he exhausted his pool of available suckers, he relied more on laundering money for the Russians and accepting sweetheart deals from Putin-connected oligarchs.