Well, ddrescue can definitely “read audio tracks” and is perfectly suited for making archival copies of Audio CDs but it sounds like the problem you’re actually trying to solve is interpreting the data as Red Book CD-DA and decoding it into chunks you call files ;)

Why does ddrescue care about "file systems"? Again, I was under the impression that ddrescue does bit by bit copying that I can then mount (and tell it the "filesystem" required).

Is this false?

I have also noticed that, sometimes, ddrescue has trouble ripping dvds, chocking out or producing a low quality rip, that will play perfectly on the same hardware with VLC

ddrescue works with blocks and bytes. Audio cds are different. They contain a single physical bit stream interpreted as several interleaved logical bit streams representing e.g. audio, position, metadata, error correction. They are not a sequence of bytes. Cdroms and dvds put a block and byte abstraction on top of this so ddrescue can do something with them.