Well...let's see an uncompressed, unfiltered, band-unlimited, DRM-less analog audio stream from a cassette,
Clearly you've never mastered audio for cassette output. Typical compact cassette tape will start rolling-off around 12-14kHz; chrome tape will get you 16kHz; metal will get you close to 20kHz. Tape ain't the holy grail, as limitations of the medium impose compression, filtering, and band limitation (just in the analog domain.)
I just checked, and I can get 100 CD-Rs for $12 retail all day long. So my band can release a single on CD in an audio-CD format, or as a data disc with a raw uncompressed bit file. I can master this from the kitchen of my apartment, just like the article says.
In spite of the article claiming "this isn't another display of analog hipsterism," oh yes it is.