I wish I could agree, dear friend, but I am afraid I cannot agree. The naturalness and lack of dryness of Sarah's voice on Fumbling Towards Ecstasy versus Surfacing I believe proves this wrong. And even if the digital-ish sound is caused by processing rather than by recording, isn't that a distinction without a difference if the goal is natural voices?
I personally have not found "plenty of digitally recorded vocals, or vocals recorded in analog and transferred to digital, that sound supremely natural." I have found two, or maybe a few. I am not sure what "supremely natural" means.
To me, it is "supremely natural" only if I am utterly unable to hear any hint or residue of digital sound or tell-tale digital "dryness." If I have trouble believing what I am listening to was actually recorded digitally, then it passes my test.
I appreciate that this is a statistically invalid sample set acquired with non-observable search criteria, but the new Suzanne Vega live cabaret release is the least digital sounding vocal I have ever heard in my entire life. It sounds so natural, so normal, I literally had trouble believing this album was digitally recorded. Prior to Suzanne Vega, I always thought Famous Blue Raincoat was a good digital recording, but, to my ears, it still exhibits a slight patina of the tell-tale "dryness" of digital.
Putting in another way, in my personal experience, I have never heard an example of converting an analog signal to digital with a result of improved sound.