Interesting thoughts, but I don't think we'll see an end to the royal family any time soon in the UK. They are far too popular, despite everything you may read from vocal abolitionists. I know we once briefly flirted with republicanism (Oliver Cromwell, the English Civil War, etc) but that was then soundly rejected, Charles II took the throne in 1660, and that was the end of that.

By the way, those weren't our last three prime ministers. Those would be Liz Truss, Boris Johnson, and Teresa May (and before that, David Cameron and Gordon Brown, before you then end up back at Tony Blair). Yes, I know it's hard to keep up. We seem to be swapping them more often than we change our socks these days.