getting a job = being a non-poser entrepreneur? I think your last point is a bit off.
The point is not that working for someone else is an entrepreneurial activity, but that experience is a prerequisite to successful entrepreneurship. School doesn't confer that experience, except to the extent that students often have a lot of spare time and access to resources. Self-motivated students who take advantage of that can do that well, but not everyone is a Gates or Zuckerberg who can afford to ignore the curriculum in favor of their spare-time projects. For most, working for someone else - which includes free-lancing or working for friends' startups - is by far the best way to learn what's truly in demand, what's truly new, what's truly possible.