I'm not so sure. For instance Marc Andreessen coded as a kid (https://www.britannica.com/biography/Marc-Andreessen) and worked as a software developer employee (https://en.wikipedia.org/wiki/Marc_Andreessen#Early_life_and...). Elon Musk also coded as a kid (https://en.wikipedia.org/wiki/Elon_Musk#Early_life) and was doing development for his earliest startup (at least). They started as computer geeks and became "venture capitalists and businessmen" later.