The thing is gold medals are relative. Relative to how well you're doing vs your team and I'm about 99% sure that the game doesn't really take into account of that as a way to measure your skill, because using such an isolated and small sample would be a pretty bad way to measure your skill in such a wide player pool.
This
"but I win a lot" is also going to happen under the same logic
It's not even a probability, we can confirm gold medals aren't the thing that determines if you rank or not, else nothing makes sense with how people have placed.