It's a terrible shame. I think the main issue is; philosophy instructs you to question everything, and schools want obedience, just like the workplace. It would go against their plan completely.

Generally, young people have such low attention spans devoting a good amount of time to a subject that never generates a clear result will also put them off.

I agree with you and you have raised a very important point. The world would be a lot better with more philosophers. We could rationally discuss ideas without offence!