Alice Walker (one of my favorite writers ever) once wrote beautiful essay on the reason we can't expect the people we admire and are inspired by to collaborate with us or mentor us. It was called something like "People are busy" and even though I have all her books I can't find it right now..I think it was on the pages that fell out of my well worn copy of one of her essay books. The gist of it is that early in her career as a writer she was acutally able to start a correspondance with Langston Hughes (this was pre-email days.) The time came when she sent him a letter and received no reply. She chewed this around in the back of her mind - why was he ignoring her, had she said or done something to alienate him, had he decided he didn't want to help young writers, what happened? What happened was that he was deeply involved in the work that he was doing as a writer, traveling around the country doing readings, and trying to squeeze in some soul-saving private time by himself and with loved ones. He hadn't abandoned her, he just had to nurture his own creativity and do the work that encompassed all his readers, not just a few.
She wrote this piece because she had gained a lot of recognition - this was right after the film "The Color Purple" had been released - and now she was being approached by more aspiring writers than anyone could help in a year of days. She was trying to explain how she loved them all, hoped her words and work would be an inspiration, but with all that she needed to do professionally, personally and as a political activist, she simply could not take individual writers under her wings.
I have been talking to and working with musicians since I was in college and a lot of fans don't know how grueling their schedules are..the new business model has shifted a lot of the work record companies used to do into the artist's responsibility and the economy has put them in a position where they have to work more for less money. There are musicians who are also music educators who teach professionally. This is something that fits some peoples' personalities but not others. I obviously can't speak for Al but all you have to do is look at his tour schedule and his journal entries on this website to see that he is doing a lot right now.
As a writer I dream of having one of my favorite writers take me under their wing - for David Sedaris to say he read something I wrote and laughed so hard he spit coffee all over his computer or for Anne LaMott to tell me how insightful and brilliant I am (by now everyone reading this is laughing so hard..wipe off your computer screens y'all) Sometimes it happens that you get to hang out with someone who inspires you - but that is usually one of those God things where you get thrown in their path and they recognize you. It never happens by force or expectation. Otherwise writers, musicians, visual artists, all of us who do creative work can be inspired by these people, see them as role models, and try to do work that touches our audiences as much as our heros' work touches us. There just isn't enough time in the day for most of them to touch us directly.