Indeed, it is The End of the queens of Numenor in more than one way. Although The Akallabeth makes Ar-Zimpharel seem like a shoved-aside princess in a movie where the villain wins, a story fragment in The Peoples of Middle-Earth changed my views on this queen some. In the (unpublished) story fragment, Tolkien proposed the idea that Miriel & Pharazon had fallen in love, and she broke off an engagement with a kinsman of Amandil in order to marry her golden prince, who became Ar-Pharazon the Golden, the Great. So she blundered, but she blundered for love, and perhaps a chance to reduce the burden on the Faithful through her influence. In that case, the rise of Sauron as Ar-Pharazon's adviser probably was the end of her power in the realm, and she could only watch the corruption of her husband and lord from the sidelines.
It is an interesting proposition. (Boy, I read them but this one I didn't remeber about) Though I always hesitate and doubt over if the material in the Peoples of middle Earth and other posthumous material is truly something he had settle d on or toyed with and later discarded. So it is rather difficult to get a clear picture sometimes.
I suppose it's just background material without a firm foundation.... But a lot of Tolkien's later writings really seemed to broaden and detail his world, even to that extent. The fragment was a teasing glimpse into a portion of the great story now all but forgotten. Sort of like that footnote in Unfinished Tales that contains just about everything pertaining to Queen Beruthial. I also confess to having liked the Miriel x Pharazon romance, if only because it represented another missed chance for Numenor, written on a personal scale.