If someone says a thing is "about" something, that is meaningless nonsense except for people who think art is reducible to a 3 word cryptographic secret message.

Saying it's "about" "cancer" is like saying Terminator is about exterminator companies. Biological malignance doesn't mean it's a secret essay about cancer, otherwise The Blob and John Carpenter's The Thing and etc etc are all "about" "cancer" which is obviously false and a silly immature thoughtless way of looking at art.