Obviously there are nuances in history that academics will continue to study - I think the last estimate that I saw suggested at least six living Pretenders to the English throne! That does not include the Scottish one still resident in France, and the current true Prince of Wales, descendant of Llewellyn the Great, who lives in Chester!
Victoria is surely a bit of an aberration. An obscure German reared country miss, dragged from the frozen outer reaches of the Royal galaxy.
If poor Charlotte had lived, a lively, attractive and and party loving girl, the map of Europe might look a bit different!
However, by and large, the Laws of Succession in the great houses of Europe remain immutable.
The Comte de Paris is still King of France, the current Prince of Prussia, Georg Friedrich is still the Kaiser, and there are still Kings of Italy, Greece and Albania.
However unlikely, any of them could be asked to return, just as the King of Spain was.
Regardless of political correctness, primogeniture rules!
Just in case it is not abundantly clear, I speak from the heart, not the head.
My allegiance is to my true leader, the guy in Chester (I am a Welsh boy born and bred) not the usurper Charles Battenberg, aka Windsor.
Seriously, like many of my countrymen and women, we would not set foot over the threefold of Caernarfon Castle, seeing it as a current, hated and flaunted symbol of oppression.