Count me skeptical about of some of these 'self-made' billionaires. Pinduoduo for example, as with many Chinese companies, has been accused of falsifying revenues to pump stock prices. Yes, this stuff happens in the US as well (we all remember Enron and Theranos), but to what extent, are the statements of these companies transparent and well-audited, and regulated by government differs by region.

And Bitmain? Is it tech wealth creation to sell pick-axes to desperate miners looking for a gold rush? This looks to me like instead, a zero-sum trade, wherein someone got rich, and everyone else was left holding the bag for a device that would be worthless in a few months.

Of all of those on the list, DJI looks like the most legit, self-made success story, producing a very high quality, Apple-like experience in innovative drone devices, devices now used extensively by the film industry.