Obviously the guy knows nothing about creativity and art.
He's not telling bands how to be successful artistically, he's telling them how to be successful financially in the modern music world.
If the band is only interested in promoting their art, they can do anything they want. If they want to earn a living too, they need to provide the market what it wants.
Generally, the financially successful artist will be touring and playing live shows and between that spend a lot of time in a studio recording many songs at once, not recording a song every month for Spotify pittance.
He's not telling bands how to be successful artistically, he's telling them how to be successful financially in the modern music world.
If the band is only interested in promoting their art, they can do anything they want. If they want to earn a living too, they need to provide the market what it wants.