"op-amps are bad for audio"
IMHO this discussion is lacking a serious point:
OP-amps are not designed for audio !!
The semiconductor industry knows very well, what is good for audio applications, and what not. Therefore, IC designs have been created, that have a somewhat similar behaviour to OP-amps but THEY ARE NOT! They are integrated audio amplifier components (wow! - or audio-whatever-functional), and are more costly than standard OPs.
One design constraint is - guess - less open gain, and less or none internal negative feedback, and a different HF compensational circuit. Another one is low noise, which has also to do with the size of the structures, and the type and pureness of the materials.
We can find audio gear that is built with OP-amps (the cheapest and least challenging to construct), and other, built with audio ICs and discrete active parts.
So, when buying, everyone professional should examine what is inside, and this will be of some help to estimate the result...
That said, I fully agree that the design surrounding of the ICs will be crucial in any case. This especially includes mechanic/geometric design and placement of all parts.