It's mostly meritocratic for the little people. 94% of UK children go to state schools, but only 50% of MPs went - and that's considered good.
A little bit of strawmanning there, implying I'm insisting on an unblemished ideal system. I simply think there's plenty of room for improvement on what we have, and stripping one family of a birthright to rule would count towards it.
I don't think it's at all clear we could get rid of the monarchy through democratic mechanisms! But that's rather besides the point - we wouldn't try, because the amount of state & media propaganda shovelled at us will prevent most people from wanting that. Unless some troubling events fast-track Harry & Meghan to the top of the succession order, of course.