This will be a requirement enforced by the Record Companies, who are paranoid about file copying from PC Hard Drives.

I.E. It's not a Tidal or Meridian decision per se.

File Cacheing is not allowed in the desktop apps of the other music services either... Except surreptitiously by Spotify, who then use your local cache to "serve" other Spotify users nearby, with the files themselves being Encrypted.

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