You're right. The kings of France have killed the kingdom of France. Maybe "corruptio optimi pessima". Hluthawig received the celestial balm and it was destroyed. So, even if there are pretendants, they can't be kings.Yes, the time of Karl der Große was quite a while back, "just" over 1200 years. While the bad relationship between "East and West Frankia" for most of the time since then has surely played a role that some nobility ranks never spread, I think the later massive centralisation of France also played a role. Even back at the time of the Stem Duchies which would become the HRE/German Empire, there were ranking structures for the nobility.
Since the XIXth century (it's an invention of that time
It was about Frankia, which is more than Frankia.