Originally Posted by Spheno
The answer is very simple. The female line grandchildren inherit titles from their fathers.
It was hard to imagine british princess's husband without a title.
It denied royal status to some grandchildren and not others based on the gender of their royal parent - titles don't come into it but being royal does.
Regardless of whether Andrew or Edward had been given titles when they married under the 1917 LPs their children were going to be royal but Anne's children aren't royal - and that wouldn't change whether or not Mark or Anne had had a title.
The following might make clear the sexist nature of the 1917 LPs -
Princess Mary married the son of Earl of Harewood so her children took titles from their father but were NOT royal - not HRH Prince/Princess while her brothers who married the daughters of Earls had children who were HRH Prince/Princesses.
That is sexist - the spouses were children of Earls - the same rank in the UK but the children weren't royal or were royal based on the gender of the child of George V who was their parent.
Going further - Charles and Anne needed special LPs to be born as HRH Prince/Princess because even though Charles was about to be 2nd in line to the throne his descent from a woman meant he wasn't automatically royal. Move on a generation to when William was about to be born as 2nd in line - no special LPs needed as his descent was through a male.
Even The Queen had to do something to ensure that a girl born to William and Kate was born as an HRH Princess as only the eldest son of the eldest son of the Prince of Wales was automatically a Prince - turned out George was a boy so not needed but without the special LPs to cover all of William's children a girl would have been born Lady xxxxx Mountbatten-Windsor instead of a Princess.
The 1917 LPs are sexist and aimed at treating some grandchildren of a monarch differently to other grandchildren of a monarch based on the gender of the royal parent.