Given the constraints of the right type of personality, geographic location, cultural understanding and network; there were very few people who could fit that criteria and launch successful companies.
Well, SEM changed all that. Entrepreneurs from all over the world could build a website, cheaply acquire customers, and build a solid business without all that extraneous stuff. (given the right type of web business of-course) They could be anywhere, know almost no body and drive traffic to their business. All they have to learn is how to buy clicks, signup for or launch affiliate programs, and optimize their website for natural search – and all that information can be learned on the web.