>>svnt+(OP)
It was wrong not because they both did achieve something. It is generally wrong and the joke just used their achievements to break the barrier for understanding that.
>>ivan_g+ob1
Suggesting that we should be on a first name basis with the romantic partner of every famous person we know of simply because they are the romantic partner of a famous person is pretty naive. “Spouse of Y” works just fine generally to save space and effort for (locally) real people.