t. Of course the Savoias and the Savoia-Aostas are the very same family.
They are very distant branches of the family though. Aren't Aimone and Emanuele Filiberto fourth cousins ?
Still, you are correct in the sense that, using the patrilineal naming convention, they are members of the same family. The tricky issue is that, using the same convention, Vittoria di Savoia's children will belong to a
different family.
If Aimone and Vittoria were both claiming the (defunct) throne of Italy , I guess that would not be a major issue. Indeed, in countries that have had cognatic sucession for centuries, including England and later the UK, the Crown passed from one family to another multiple times and it is reasonable that Emanuele Filiberto would rather have his daughter succeed him than his
fourth cousin.
The problem is, however, that the question here is not succession to the throne of Italy, which unfortunately was
irrevocably abolished by the republlican constitution of 1947. Instead, the dispute between the two branches is about the succession to the position of head of the family and grand master of the Savoy orders and, in this case, it is somewhat odd that Vittoria di Savoia's descendants should become heads of a family to which they do not belong.
As pointed out by other posters, merit of course is not a prerequisite for hereditary succession, which is inherently non-meritocratic. But, if merit is to be discussed, especially if we were discussing who would be best fit to be King of Italy (something that is now constitutionally impossible under the Republic), I am afraid that neither branch scores high marks.
Marengo mentioned Emanuele Filiberto's claims in the French TV documentary Royals at War that his grandfather was somehow forced to cooperate with Mussolini, or else he would have been deposed and replaced with the Aostas, who were "notorious fascists". That is not a new claim and is part of the revisionist narrative that the main branch of the House of Savoy has been trying to push for quite some time. Unfortunately, that is not true, or, to give the Savoys the benefit of the doubt, at least it is not entirely true. In other forums, I mentioned multiple occasions when Vittorio Emanuele III could have removed Mussolini and would have been backed by the Italian establishment and the military, but chose not to do it.
Of course, Vittoria di Savoia, a 17-year-old teenager raised in France, is not guilty of the sins of her ancestors and it is not fair that she should be punished for that or, indeed, for the questionable personal life of other more recent members of her family.