@Labradorandshiraz
I think I understand where you are coming from with all this. In summary
(1) All children of the Sovereign can be called a prince or princess;
So far so good. All 4 children of the queen were called by their titles.This is still the case now that Charles is King.
(2) Those children, whose father is a son of the Sovereign, can be called a prince or princess;
Ties in with the above. However, it excludes Anne - who was not the son but daughter of Sovereign. It does however include Edward. Who may have chosen or told not to use the titles for his children. Certainly Andrew choose to use this right for his children.
(3) The eldest son, of the eldest son of the Prince of Wales, can be called a prince.
This is the tricky one that was changed. Because it technically says only George would be prince, till Charles takes over.
We were told about how Charles wanted to slim down the monarchy. If that was the case this rule would have been changed to
3.1) The eldest child (be it male or female) of the eldest child (once more, male or female) of the Prince or Princes of Wales, can be called Prince or Princes.
This way, if Charlotte was born before George, only she would be called Princess and younger siblings George and Louise would wait till Charles comes to the throne.
Now, according to Harry and Meghan, the palace were looking at the patents and wanted to change the rules for Harry's children, so that Archie and Lili once Charles comes to the throne, they would not have the titles.
People excused this for slimming down titles. If that was the case, then why was this not changed as above in point 3 for all children.
Now don't forget that Charles was announced as King and William as Prince of Wales as soon as the queen died. It took 9 months of public complaints for Archie and Lili to be publicly acknowledged - which arouses suspicions from a lot of people.
On preview this now has paragraphs.