Andrew was first described as a minor royal shortly after Harry's birth while he was still very popular and Fergie wasn't in the picture.
Harry is lower in the line of succession.
If people were describing Andrew as a 'minor royal' when he was 4th in line, the second son of the reigning monarch, the brother of the next king etc then the person who is 5th in line and about to drop to 6th, grandson of the reigning monarch, second son of the next monarch (the position currently held by Andrew - a minor royal), brother of the King after that (a position also held by Andrew), uncle of a future King (again a position held by Andrew).
Whether a person is a major or minor royal is NOT determined by their relationship to the monarch but by their place in the line of succession. As Andrew has been described as minor since he dropped to 4th then it makes sense that the current 5th and soon to be 6th - who has never been as high as Andrew has - is also a minor royal.
In time Charlotte and the new baby will also be minor royals.
Charles' plans are rumours you realise based on a throwaway line made in 1992 at the Way Ahead Group meeting which is now disbanded. It has never been confirmed but makes sense given the fact that the British public see a bloated royal family. If Charles genuinely is interested in 'streamlining' the royal family then he needs to start with making a clear distinction between the heir and the spare/s so that William is a Duke and his children are HRHs while Harry is an Earl with children styled as Lords/Ladies.
What happened with Andrew 30+ years ago was BEFORE the suggestion of a streamlined royal family was even made and so is irrelevant. What happened with Edward's title is more relevant as it was made clearly AFTER the suggestion was made - but William and Kate having three children has also thrown a spanner in the works as that will again see a blow out in the number of royals unless a line is drawn in the sand - HRHs for the direct heirs only and not the spare/s so HRHs for William's children but not Harry's - or anyone else's in that generation and follow that with HRHs for George's children but not Charlotte's (who don't qualify anyway as they will be descended from a girl) or the new baby's.
You do realize the streamlining happens Naturally. There are 14 working royals a the moment. When Charles is king, the Gloucesters, Kents and Elizabeth will have retired or passed away. That will leave
Charles and Camilla
Cambridges
Harry and Meghan
Anne
Wessexes
Andrew
It will be nearly 30 years before George and his siblings pick up full royal duties. Ten working royals is already a substantial drop from the working royals we have now.
People wont stop complaining with streamline. Especially when they realize less royals doesn't mean less money. The sovereign's grant doesn't depend on how many people they are supporting. Many of the working royals currently don't have RPOs anyways. The people are going to be paying the same money for less work, less appearances. If anything, the image will not be helped by streamlining.
There is no reason to believe that dropping Harry to an earl is part of streamlining. HRH doesn't equal a pay cheque. An earl doesn't get paid less then a duke does. A HRH doesn't remotely, ask the Yorks, ensure that they will be working royals. Even if Harry's kids are HRH, in no way would that mean they would be working royals nor they would ever get any money for their duties either.
When Charles is king there will only be 2 children of the monarch. Nothing will change that. And no reasonable proof to think that he would have only one of those as a duke.
I get when people who know nothing about royals get excited about kicking out royals and think it will save so much money. I don't get though how posters seem on that path.
Again Andrew to this day is not a 'minor royal'. He is simply not very popular and gets publicity only for scandal.
Maybe in thirty years or so you will get your wish and Harry and Meghan will become the garden gnomes of your dreams, statues growing moss in the palace gardens as forgotten by anyone important.