We don't have the Forbes 4 million to view. But for every Zuckerberg on that list there are more than a few members of that 0.1% from members companies on that list.
I am not doubting that the financial industry influence is quite concentrated compared to others, but I am not convinced he's totally proven his case. Maybe the firm he represents has an outsized proportion of financial people as their clients.
Look at the filings for big companies. Usually the top incomes and options are given to the CEO, COO and CFO. CFOs are often sitting on large sacks of money and directly participating in the finance industry. Even companies with no other ties to finance or banking are usually playing around with the same mechanisms as hedge funds, banks and other investment organisations. You are making the mistake of thinking the only income a business makes today is from its core products and services. Most large businesses are making plenty of income from interest and investments if they aren't overflowing with debt.
The Forbes 400 represents the top 0.0000132%.
Sure, maybe entrepreneurs are the majority in that group, but don't trick yourself into thinking the other 1.5 million in the top 0.5% are too.