Why would there be no mechanism for decoding FLAC? It’s just an algorithm, if somehow we misplace all of the exes we can just write a new one, it’s not even proprietary technology, it’s a completely open format. And if we lose the capability of hanging onto the descriptions of basic compression algorithms it’ll probably be because of some civilization wide catastrophe and we’d have bigger things to worry about than decoding audio archives. Your argument would equally apply to PCM audio as well (and there are multiple ways of encoding PCM), they’re all just data formats.
