You obviously know way more about the specifics than I do, but (drawing again from my own engineering experience in other areas), the key question is "compared with what"? If all the pros use similar DS ADCs, everyone's ear has become trained on that technology's artifacts. For instance, much that I (mostly) love ECM's "house" style on my living room or headphones, its overall smoothness is to my ear quite artificial compared with the edgier, livelier experience of listening to the same musicians live from the front row at SFJAZZ or Yoshi's. Of course this may have nothing to do with ADCs rather than the other technical and production factors you mention, but it's just to say that we are all talking about an artificial construct where the producer's choices are bound by tradition and expectation probably way more than by strict technical accuracy criteria.
That's a great point of reference because SFJAZZ is a place I volunteer at sometimes, as well as the SF Symphony / Opera. I don't know what Yoshi's uses.
The main concert hall at SFJAZZ uses a
Roland S 2416 digital stage unit like I posted earlier (the little labs downstairs don't need it). It has sigma-delta/delta-sigma chips inside it.
So the 'livelier' sound you hear has pretty much nothing to do with the ADCs. It's all in the mic choices, the acoustics, the EQ/DSP/DRC, and in the mix. Although, in the case of a front row seat, you should be hearing more direct acoustic sound and less from the PA system.
ECM's house style has pretty much nothing to do with their ADC/DAC choice. It's all in the other aspects. Their 1970s all-analog recordings have the same ghostly sound.
The producer's expectations for an ADC are the same as for cables and amps. It should be transparent.
The technical reference is the live mic feed, i.e. how close does the un-coverted, all analog chain sound vs the digital one? That's pretty much as good of a reference as you can get -- better than a master tape.
The lack of obsession over ADCs isn't due to 'tradition', it's due to the ADC being viewed as a solved problem. Think of it this way: once upon a time, IT guys cared a lot about the NICs installed in PCs because of issues relating to drivers, IRQ conflicts, etc. 3Com built a huge business around it. Now nobody worries about such issues. They're solved problems and everybody uses whatever NIC/WiFi chip is built into the motherboard of the computer. It's not because of tradition, it's because it's not worth worrying about. They're all viewed as good enough.