We have to stop pretending degrees are worthless. The way I see it, going to school, expedites your learning process, by exposing you to professors and your peers, it helps you learn best practices, which although generic, saves you a lot of time making same mistakes others (your professors and your peers) have made. Also it gives you the focus and urgency to finish your learning on time.
As an analogy, consider the knowledge accumulated while atending school as open source software, even if your knowledge or the OSS is generic to be fully usable for the task at hand, it almost always gives you a big headstart to get your job done, because it avoids the trivial and non-trivial pitfalls through years of maturity.