The Nike commercial was especially dismal. But at that point, Bill didn't need to prove himself to anyone. If he needed to do a Nike commercial to pay the damn rent, more power to him. In a hundred years, no one will give a damn what Nike was. But they'll remember William S. Burroughs.
Nothing is true.
Everything is permitted. In a way, maybe he didn't die, maybe he did just fade off into the cold gray mist. Burroughs' passing was so unnoticed as to be irrelevant, but his discoveries inevitably remain in the spaces between words and images and thoughts. His books gather dust on obscure library shelves, but the ideas they contain are very much alive in the minds and work of countless individuals who have sought inspiration from his explorations. Do some exploring of your own.