I think you'll find that thermal noise makes up the greater part of ISO noise whether it is amplified after the fact or generated on-chip during capture.
Do you have any source for that? I asked Eric Fossum, inventor of the modern active pixel type of CMOS sensor and still working in the CMOS sensor industry, in a DPReview forum discussion, and he confirmed that to the best of his knowledge (vastly greater than yours or mine) thermal noise from within photosites is not a significant factor, as it is greatly overshadowed by amplifier noise. (Except in long exposures, when dark current noise accumulation can be an issue.)
Also, as soon as the illumination of a pixel is half-way decent, about 100 photons or more detected, photon shot noise overwhelms both read noise (mostly amp. noise) and thermal noise.
can you please point us to ANY consumer CCD camera that outperforms a current consumer CMOS camera on ISO noise?
I do not see the point of that question since no-one is disagreeing that modern CMOS sensors outperform CCDs at high ISO. The only disagreement is about the reasons for that advantage. My answer: mostly a better approach to amplification allowed by the active pixel approach of modern CMOS sensors vs the passive pixels of CCDs. By the way, once upon a time there were "passive pixel" CMOS sensors, but they were only useful as a cheap but noisy low end alternative to CCD's.