No doubt it is possible to make discrete stage of good quality but stating that op amps have inferior sound quality compared to discrete stage because of the "simpler" signal path, higher feedback or something else is simply BS.
The truth is this: discrete stage of the same or comparable quality as the one made with op amps will cost significantly more and I see no single reason to pay for it as it will not sound better.
I disagree. Discrete opamps have advantages over the monolitic simply because real estate is not limited.
An excellent whitepaper https://sparkoslabs.com/audio-op-amps-gain-seek-bandwidth/
Internal testing with discreete stage reached -114.4THD+N unweighted and I think that unmatched in all tested DAC (unbalanced at 2.1Vrms) (but with special LPS for 5V)