1996. Before you could listen to every kind of music from everywhere at any time on Youtube.

But he is still alive, isn't he? I hope he has heard the tunes by now. With sites like https://c64audio.com/ and Kickstarter projects like https://www.kickstarter.com/projects/c64audio/back-in-time-s... there has been quite some public visibility of SID music.

For what it's worth I'm sure he's aware of music made with his later inventions at Ensoniq (which made the first low-cost sampler, as well as some of the most popular synths of the digital era of electronic music...huge swaths of the late 80s through mid 90s owe their sound to Ensoniq synths and samplers). The SID was a breakthrough for microcomputers, but it wasn't widely appreciated in the music industry, but his later work certainly was.