The usefulness of a degree depends on what field one is working on. In the Software arena, smart kids out of high school can do a lot if college is not holding them back. But try to start a laser / semiconductor / biotech company with high school kids if you dare ;-)
One might not need a degree to be a good software entrepreneur, but there are many other entrepreneurs who don't live in the software world. Sure, HN is focused on software, but it seems to me that it's irresponsible to promote the idea that all that entrepreneurs need is passion and hard-work. Necessary but not sufficient.