I disagree with this bit, there’s plenty of sources who give some credibility to Fentonius’ interpretation.
There are several hints that dragons dissociate their true form from their mortal avatar, and they very much prefer their natural form:
In War of the Ancients, Krasus feels “trapped” in his mortal form, as he is unable to transform back into a dragon. He explicitly regrets being unable to fly, defining himself [translated from italian] “a creature of the sky” (in opposition to his current, wingless form), and if memory serves me right, he even dreams about flying.
In Twilight of the Aspects, when Thrall reaches the Nexus, Kalec and other blue dragons take humanoid forms. The one who doesn’t is Arygos, who points out that he shouldn’t do that out of courtesy for their guest - his gesture is depicted as a lack of kindness/respect towards Thrall, implying that normally dragons don’t take mortal forms in their lairs and those who did, did so only out of courtesy (ie. Thrall being there).
Multiple times in the old lore dragons are depicted as having a bias over humanoid races, which they see as unreliable:
During the WotA, DotD novels and even some WotLK dragon bosses refer to non-dragons as “lesser beings”, implying that several among them don’t think that highly of humanoids.
This is further confirmed by other Aspects being moderately annoyed by Kalec’s tendency to prefer his Visage’s name rather than what is defined his dragon name: that is, Kalecgos. This also implies that most dragons hold a strong distinction between what is their disguise and what is their true form.
Further expanding upon this: always in the WotA we see dragon agents spying upon the kaldorei empire - red and blue, respectively. Both don’t think very highly of mortals, and if I recall correctly both make a few remarks in regards to the elves’ arrogance.
I think that what Fentonius is referring to, however, might be Kalec explaining to Anveena the lore of dragons. Once I get home I will check the manga out.