Let's just say for sake of discussion, CD and Vinyl are equal in reproducing sound.
This equality starts to give way even after the 1st play on any
turntable, no matter how well balanced & built.
After all, vinyl is relatively soft, compared to the diamond stylus. No mater how well implemented the turntable, stylus weight & tracking balance are set, the centrifugal force from the stylus which can get “substantial” towards the end of play, and will wear
out the outer groove or right channel more than the other.
The addition of surface noise from dust, mold, all exacerbate the problem.
This is not to say all CD's sound great; they don't.
Many CD's are poorly engineered.