Tis your point about about a high note "as a listener" stands equally for a fast passage by a guitar. If a listener doesn't know about the work involved, a technically difficult passage sounds all fluttery and pretty (and, probably should sound like that). Anyone who has ever played knows it's not, but a listener who has never played shouldn't know better; similarly, even knowing that he was probably born with a naturally high range, the effort required to create that note is phenomenal to me.
(which is to say, if people in this forum are allowed to say "dat bass"/"dat unison" etc then I'm allowed to say "dat note")
Personally, a singer singing a climactic high note off a run like that pretty much socks me in the stomach (from the final "vincero" in nessun dorma; or the final "night" in "o holy night" - I'm a sucker for it) and I'm glad that singing like that affects me in that way. My initial point is that that is a virtuosic moment, that matches (and for me surpasses) all the instrumental pyrotechnics that are happening elsewhere in the band,
In terms of the virtuoso argument, I gather that you think rapid passages equals virtuosity, but rapid vocal passages have actually been out of vogue for about 200 years now. Your 19th century Wagerian singer trades vocal nimbleness for vocal power (due to the loudness of the orchestra), and I say this because I don't think you really get how huge James' voice is. James voice is huge. Seriously. The appeal with James is that he is your singer with age old vocal technique, using his diaphragm and breath to project (the basis of classical vocal training) combined with a huge range. For me, I love that I can hear James' body in his vocal lines.
The inconsistency that you have cited previously would not occur if a DT concert was an hour each night because the voice is a muscle, and muscles get tired (unless you're making pretty sounds into an electronic amplifier system). If you have ever sung, then you would know, once your high notes are gone, they're not coming back, and he manages that each time he sings. So, what he does is pretty incredible to me.
In conclusion, I really disagree with you saying "James is not a virtuoso" because you are not showing me that you have an idea of what the technical challenges in singing are.