There seems to be general agreement that public objections to the Duchess of Cornwall being known as Queen in some form can be blamed on the memory of Diana, Princess of Wales, and that over the years public opinion has come to be more accepting of using Queen for Camilla, but the issue is more complicated than that.
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Second, while the Duchess of Cornwall's approval ratings improved, the improvement did not translate into a preference for Queen over Princess Consort. According to the latest YouGov poll on the title issue (April 2021) to be taken before Elizabeth's announcement:
Third, while the preference for Princess Consort in April 2021 is typical of the polling through the years, a YouGov poll in June 2014 presented the question and options differently than in most polls, and it resulted in a majority of the respondents expressing support for the Queen option.
https://yougov.co.uk/topics/politics/articles-reports/2014/06/10/Camilla-can-become-Queen
In the UK, when a king is crowned his wife typically becomes queen consort. Thinking about if Prince Charles becomes king, which of the following comes closest to your view of his wife Camilla, Duchess of Cornwall?
53% She should become queen consort, as is traditional for a reigning king's wife in the UK
32% She should be given a lesser title, out of sensitivity to Diana, Princess of Wales
14% Don't know
What that atypical result suggests to me is that there is a significant segment of the public which wanted the lesser title for reasons
other than sensitivity to Diana, Princess of Wales (which is why they did not choose the second option), and/or were not aware that Queen is the traditional title for a reigning king's wife in the UK (which most polls do not explain).