This change is completely unnecessary and will only make the game very frustrating for a lot of players. I know that the current rating system is not perfect, but it is far better to leave it as it is than making it even worst. I am also one of those players who remember playing without the win streak and it was a truly horrible experience which was taking away almost all fun from playing the game.
Also, I'm pretty sure that this will change nothing at the very top of the rating. Why? Because the best players already have a win ratio of around 80% and more so this change will not affect them much. But it will affect others who will try to catch them.