Then why would you do that? If you recognize it’s not right to expect that, why would you specifically want a partner that absolutely loves your body?
There are very few examples for likeable female characters, for example, who aren’t also beautiful and young.
Because, as we’ve been saying, most characters (whether males or females) in fiction are beautiful. There’s also very few examples of likeable male characters that aren’t also beautiful.
You might have a point with the age but I’d attribute that to historical Hollywood stars being mostly male, as more popular actresses get old we’ll definitely see more likeable old women.