The advantages that initially motivated cassettes over vinyl back when cassettes were invented are basically still valid, for example that you can't have a vinyl-based "walkman", and that they're economical to record onto, while pressing short runs of vinyl is not economical.

Indie acts have often gravitated towards CD-R rather than vinyl, because they can burn them at home in small quantities. But for mobile use, a walkman actually beats a discman, in my opinion, due to its smaller size. And, not being digital, cassettes have a kind of built-in "soft" DRM feature, in that reproduction is possible but goes hand-in-hand with a loss in quality. The mixtape / pirating / bootlegging scene helps spread the message about an act, and, if someone truly likes the music, they might go back to the original artist and buy an "official" prerecorded cassette where they get better sound quality, and a reasonable level of expectation that the money actually reaches the artist to support them.

With Spotify, for example, I have no idea, as a consumer, if I listen to a lot of small acts, how much of the money I pay every month to Spotify actually gets into the pockets of those acts, or whether they're just on there because they got arm-twisted into being on the platform because of platform power.

There's a lot that's good about the medium, and that goodness comes in the form of simplicity in engineering, which is a virtue in its own right.