The sound quality from TIDAL/Aurender is very, very good. But, CDs played through a terrific transport/DAC combination always sounds better.
Saying CD’s always sounds better is bit of a reach. This may very well be your experience with certain recordings but simply not possible across the board. I have heard and compared recordings on both formats and they both can sound stellar to mediocre. Why? Because of provenance and mastering of a recording. They are the key differentiator between us loving or hating a recording, IMHO.
My system - Aurender N30SA ➡️ Merging Technologies DAC with external power supply and both DAC and N30SA are synchronized by external Merging +clock.