They're both wrong! First of all this aim high stuff is nonsense. Facebook did not start with the goal of toppling MySpace. Microsoft did not start with the goal of running on 95% of machines. Twitter did not start with the thought of becoming a billion dollar company. These companies get their through consistent cycles of ambition and execution. There's nothing particular about a "lifestyle" business other than that the ambition has waned. There's literally no business that exists that can not have ambitions and grow into a major corporation through a series of growth cycles. Likewise, there's no business plan for a billion dollar company that someone can draw up from day 1 and have it survive the market on its way to that size.
As for education, that's the qualification for knowing how to run a business? There's nothing about growing a business from nothing to 9 figures that a few years in the trenches of silicon valley won't teach you better than education. Sure higher ed can teach you a lot, and you can make a lot of connections, but there's nothing special about it, and in fact it doesn't really have the same culture that makes successful startups possible. My advice to anybody in college with a project as successful as Facebook was at the time Zuckerberg dropped out is, "yes, you should drop out too. You won't be the next Zuckerberg (that ship has sailed), but you'll likely meet with some success in the valley, and certainly you'll learn more about running a real business than you were going to finishing out school."