This is a salient point. I've personally found that most junior/intermediate people want to be mentored but it should always be done carefully and with consideration. I've had a couple of junior/intermediates, though, who, like you are saying, just did not want it. I think that most of them have moved on from the company but there is 1 person who is still around and who is now the type of person who has 5 years of experience but it's all the same year.
Mentoring is one of my favorite thing. Finding people who want to be mentored is...challenging though. Probably a chicken and the egg (one of the other posters mention how people are put in a situation where they can't be open about not knowing things), but so many entry level engineers just pretend they know everything.
Completely agree with you though that this kind of dynamic would drastically improve the industry.