(https://www.royal.uk/the-royal-archives)
It's not that long ago that the Palace took the position that The Queen was exempt from taxation because it was raised in Her name, the implication being that she did not exist privately. Although, now, it seems to recognise a distinction between the monarch and the person who holds that position, that issue is far from clear.
Whether or not the records of other members of the Royal Family should be subject to preservation and, eventually, public access for certain purposes (biographies, historical analyses), might/should depend on whether or not they were, to quote this new category apparently loved by our King, 'working royals'.
377