Rules about such tihings get adjusted, and presented as being traditional even when they've only just been invented .

The term "Queen Consort" has never been used for ay previous partners of Kings. Nor has Princess Consort. Prince Albert was the only partner of a queens regnant to be known as Prince Consort, and of coirse Philip never had the title.
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Actually, in some ways I'd be more inclined to use the expression "naive" of Charles rather than Diana. But I've never really got itnto Palace gossip. I tend to see them as part of the landscape of this strange country.