I would say that Gary Busey living to the age of 70 (and let's hope for another 30 or more for this fine gentleman) is an accomplishment worth celebrating.
To me, the quintessential Busey role was his small piece of acting in Thunderbolt and Lightfoot. In the film, he plays a character named Curly who works putting lawn sprinklers into various rich people's yards. The way that Busey played that part suggested to me that he was very much into it, and that you could watch that film and see his performance and then not be surprised to see the character still installing lawn sprinklers to this day.
Busey is much derided and mocked, but no one sells a character like he does. He lives inside of the parts he plays and believes in what he's doing. He will chew up the scenery and roll in and out of dialogue like he was born to do what it is he does.
Amen for great actors. Gary Busey, contrary to what the shitheels and prudes and hipsters think, is what a great actor does, no matter how lousy the part. And, by lousy, I speak of course of Quigley, one of the strangest films you will ever see--one that involves Busey convincing everyone that he is, in fact, a dog who has been reincarnated as a human--or is it the other way around?--in order to atone for being an asshole.
Do not watch this film with children, even though it is one of the few family movies Busey made. Watch it alone, and then burn your memories.