He claims further down that some make 50k per day. I've met a lot of cashed out founders. I've even met someone who could be called a billionaire. None of them were pure software engineers that made "50k per day" at any point in their career. If you amortize what becomes a 50m grant over 4 years it's about 35k per day, but how many software engineers have done that?
For anyone that came to the comments before the article, it claims that number is per day