It's a difficult one. It seems obvious that fame has costs for people but we don't know that that is the, or even a cause, in individual circumstances. There's no guarantee that had Elvis walked away from fame after That's Alright Mama, that he wouldn't have been dead by 42 of some addiction.
I think we need to be aware that it isn't necessarily a boon, and that we are often too judgmental of those in the spotlight but not sure there is a way of avoiding it.
One of the ancestors in my family found fame, he drank too much and committed suicide. But he was far from the only one who drank too much, and not the only one to commit suicide.
I'm not sure whether what happened with Karen Carpenter is, therefore, that relevant to how unusual or innovative they were.