This is the crucial part. to regular users. The platform streams audio using lossy codecs (AAC or Opus) at relatively low bitrates.
Remember the mantra: Garbage in, garbage out. A FLAC file is only as good as its source. YouTube is a lossy source. Therefore, a YouTube FLAC is a contradiction in terms—a large, space-wasting file with the fidelity of a 2010 MP3. yt flac
If you want , consider these legal, high-fidelity sources: This is the crucial part