Yes it’s because a branch of the family left the battlefield breaking off an agreement so at that point Russia just decided to annex Georgia. Yes, but just like in the early days, there’s still division between two branches of the dynasty and the issue is Russia’s position
The Bagrations were not given mediatized status, the Georgian kingdom was simply annexed into Russia. There is a precedent of a divorcee with unequal status not being an acceptable bride, Olga Karnovich, second wife of Grand Duke Paul Alexandrovich with descendants not having succession rights ...
The marriage was morganatic because Maria Vladimirovna’s mother had been married before and was divorced with a child. The Bagration dynasty was long deposed and was absorbed into the Russian nobility in spite of its antiquity. Plus Leonida’s mother was from untitled Polish nobility.
Zara will inherit jewels from her mother who in turn inherited from the late Queen prior to her passing. I’m sure they got something from their grandmother but we will have to wait and see.