The author is stating that not all music sees distribution on Spotify et al, instead it is distributed via Bandcamp or other sources. A lot of older material isn't available through Spotify et al due to licensing issues, or labels that have gone bust.
It's their tone, there is a difference between "a lot of older material isn't available on Spotify" vs saying that Spotify has mind numbing music.
Spotify to my knowledge and experience has an enormous amount of older music. Enough to make it the main source of music for my parents. I think this guy needs to realise that they don't need to listen to the curated playlists...
