I hear you... but 3 points -
- AlphaZero can blow him out of the water if google chooses to engage in trading;
- retail guys with limited resource don't have much chance to replicate this guy's success...
- and who knows how long he can sustain... funds blow up all the time after some success.
I would not expect anything like AlphaZero do much in terms of alpha. There is a variety of reasons why deep learning has very little application to trading (aside from maybe image analysis). However, considering that Google holds all sorts of private data for all sorts of companies, that's a much bigger edge should they decide to exploit it. Of course, the moment they do that they will lose both that business and the information that comes with it.
A retail guy actually has an advantage when it comes to systematic trading since his liquidity requirements are much lower and his mandate is literally "do anything that can make money". This said, if I were a retail guy, I'd not bother with anything latency sensitive, there are plenty of other stuff to do that's less technologically involved.