That whatever skills you would learn in those last few years is not worth a few years head start on what you were going to do?

I think in a lot of domains (engineering, business, management, marketing ...), you can get a skill level better to what's taught in higher education through work experience and self-study, in the same time.

However higher education may still be worth it for the credentials (an effective way of signaling skills to employers, though you can also find non-credential way of signaling skills), and networking and connections (again, there are ways to have those outside education).

Also, sometimes it can be harder to get a job that could teach you the skills without a degree.