Indeed, the roles tell you nothing extra. You can investigate that by yourself. But the roles are there for the less active users, who don't (want to) spend hours on scouting opponents.
It makes it easy to scout how close games were? What? I've never heard this before. Why do you want to know if you had a close game? You've lost or you've won. Would it make any sense whether it was a close game or not? I don't think so.
I think it's useless.
But hey, maybe the BBs look at this suggestion in another way.
When I run into an invisible spider web, I instantly become a kung-fu master.