Don't you think that the "rolling eyes" are a bit much, and rather disrespectful to Ms. Cohen? First of all, people have lives that are independent of their parents, no matter how famous those parents happen to be, and Ms. Cohen has no obligation to share the limelight with her famous father nor to be publicly involved in his life/legacy if she chooses otherwise.
Second, while I cannot speak for you, I have no idea how involved Lorca may be behind-the-scenes, and although you are clearly implying that she is completely un-involved with things related to Leonard, I certainly have no knowledge nor evidence to support such a conjecture.
There is also the fact, of which you may be unaware, that Lorca has actually been quite publicly involved in Leonard-Cohen related activities on at least two occasions in the past year: she was on hand to accept, on her father's behalf, both his Grammy Award for You Want it Darker, and his award to Canada's Walk of Fame.
Perhaps your negative judgement of Ms. Cohen's apparent (to you) lack of involvement with her father's life is thus rather unwarranted.