Here’s the one of the good things sports can do - the team (or athlete) that gets whooped can be inspired to try harder. And the day they avenge a loss, win a championship, etc. - in some ways it’s a greater victory. It means more.
It’s the stuff a participation trophy doesn’t give you.
I think the real reason all these stories abound, is because the world hates a winner. Especially when it's the USA.