The predicate nomiative is son. Hope this helps!
This quote means that humans can always find a flaw in someone else in order to make themselves bigger than others. People refuse to let go of flaws, they believe in an idea of perfection and so we say blue eyed blondes are beautiful versus saying we are all beautiful in our own way.
In simpler terms, we refuse to see our differences as perfect.
I would rather come from old money because that insinuates that the money was probably inherited and so you never really needed to work to gain that money. You are automatically set from the beginning itself and so its easy. Gatsby had to work hard to make all the money he has and still he gets no respect or true reward whereas Tom gets all the respect and loyalty just because his family had gave him a good foundation and reputation to start with.
He died while he was running from the monster