Just another junkie making bad art.
Why "bad art?" I don't own any of his paintings and don't aspire to, but he was a talented illustrator who developed a style that sold. Nothing wrong with that. Norman Rockwell is the comparison that comes to mind.
I suppose that Kinkaide had at least three strikes against him in the eyes of the arts establishment. He painted "pretty" pictures. There is nothing transgressive or political in his art, unless nostalgia is deemed to be political. And he sold, which must raise the demons of envy among most of our "serious" artists, who are running a scam and must know it.