Well, it's hard to think of it as insulting or anything, and I wouldn't call it a lack of Carrie as a person; she was wealthy, famous, and people loved her because she was Princess Leia. She was and always will be remembered for being Princess Leia. And I don't think Fisher would mind people still calling her that, in fact her latest book that she basically died promoting was "Princess Diarist" after all!
I agree with the guy you were responding to, though, that she was "ok" in Star Wars but should be remembered for other things. While we are talking about her, and not to be negative during the time of her passing now... she was kind of "meh" in Star Wars. In Episode 4, she was a hungry actress; she had afire in her eyes, she was passionate and put some energy into her role as Leia. Episode 5 and 6, I didn't see quite that fire in her eyes. Dare I say, she looked almost bored in some episode 5 scenes, despite the undying love for ESB. Carries' best SW performance IMO was in Episode 4 and I don't feel any of the other movies she really ever had the same fire.