We are not talking here about punishing Harry and Meghan, we are talking about changing the inheritance laws of the British Royal family and IMHO Charles will never do something to lower the status of his close family. You don't know if such a diminishment will lead to an erosion and where this will end?
By "inheritance laws", do you mean the rules on the use of royal titles and styles? If so, several monarchs in Europe have been doing it for quite some time:
- King Harald V decided that Sverre Magnus would not be an HRH (only a plain Prince) and that Princess Märtha-Louise's children would be untitled.
- Queen Beatrix decided that Prince Constantijn's and Prince Friso's children would only be counts/countesses and not, for example, HH Prince/Princess [xxx] of Orange-Nassau (as, I believe, was still possible under the Law on Membership of the Royal Family).
- King Juan Carlos decreed that children of Infantes/Infantas would have the consideration only of Grandees of Spain with the style of Excellency and that only the children of the Prince of Asturias would be HRH Infante/Infanta (previously, children of Infantes were Infantes too).
- King Carl Gustaf stripped CP's and Madeleine's children of the HRH (previously all persons in the line of succession to the Swedish throne were HRHs).
So they have all "downgraded" the status of members of their families compared to previous practice. How would Charles be different if he did the same? Not all members of a monarch's family have to be royal. The cut has to be made somewhere and, nowadays, a grandson in collateral line is normally pretty far from the throne and not expected to become a state-funded working royal.
I don't know if Charles
will make any changes and, as I said, I doubt he would discuss any change plans with the Family while the Queen is still alive (since royal titles still fall under her prerogative exclusively). Nevertheless,
if he made any changes as King, e.g. to his grandchildren's titles, I doubt it would be seen as something scandalous or interpreted as any form of "downgrading" of the family's status.
It's very interesting & surprising how a title seems to be so useful in the US. I'd always presumed the US was immune from that sort of thing when it came to serious issues like work.
Yes, old school textbooks, when discussing inbound immigration in the 19th and early 20th century, used to brag about how America was a land of opportunity where family name did not matter for upward social mobility (based instead on hard work and merit). That supposedly contrasted with the rigid social class in Europe with its landed aristocracy and titles.
Of course, those claims were always questionable, especially that "family name" or "family fortune" (I am not talking about "titles") didn't matter in America, but it is still part of the idea of the American dream, even for recent immigrants today.