Well, the fear he was talking about is just using Napster as an example. This piracy still exists, and as he said, the tech improved so much that you can easily illegally share an album.
What actually stopped wide-spread music piracy, was easy to use legal solutions like Spotify.
It's as Gabe Newel said, to fight piracy, just provide a better service.
But it makes you wonder how many of today's unicorns will still be around in 20 years.