How to meaningfully audition speakers??

It has nothing to do with analog vs. digital, specific mics, multi miking or even the experience of the engineers. There really is no simple answer and therefore no simple fix.

Basically it has to do with differing aesthetics. How a classical or jazz recording is supposed to sound is very clearly defined. For jazz it should sound like "Kind of Blue", one of RVG's Blue Notes, or maybe like an ECM recording. Because jazz has such a well defined sound there are a whole list of things you don't do when recording/mixing a jazz album. For instance you wouldn't use a non-lin reverb on the drums. No compressor on the bass. No vocoder effects on the vocalist. Don't shift the sax from the left to right channel during his solo. There are just things that you won't think of doing on a jazz recording. There are no such rules or prohibitions in pop/rock recordings. Because of this the sound of pop/rock recordings is very variable. For some engineers it's a case of too much freedom and the sound quality can suffer.

Ultimately, talented musicians working with talented engineers are more likely to make good sounding good music than other combinations.

Learsfool, perhaps your disappointment with modern recordings is inherent with what constitutes a modern pop/rock recording. With rare exception they are purposely not trying to capture a acoustic instrument in a real space. Modern recordings are multitrack collages rather than some document of a real event. The tools used to construct these collages while not unique to pop/rock, don't really travel well to recording other music types. It's not that these techniques, methods or aesthetics are "wrong", but rather they are not artistically appropriate in other musical categories.

Outside of audiophiles you won't find too many people obsessed with the sound of real instrument in a real space as a critical goal in music reproduction.

My apologizes to the OP for continuing to not discuss the original question.

Multitrack recording and digital recorders are two separate issues. Multitrack recordings originated in the late 1950s and continued for decades with analog tape machines. Digital multitrack recorders didn't become available until the mid-1980s. You can make purist, audiophile oriented recordings with either analog or digital equipment.

Here's a link to an interview with Rudy Van Gelder. I take it as a fact that RVG knows more about music recording than anybody participating in this thread.