If you're a psych student, you should probably have learned that - by and large - neither positive reinforcement nor negative reinforcement are even remotely as effective as a combination of both.
When it comes to positive and negative reinforcement I have a unique view of this, being a business consultant. Almost every time I start to give a review: the problem of what to do about people who don't follow the rules comes up first.
I tell them that they need to draw a line and come down hard on the ones not doing as they should, you can add things later. The next thing I tell them is to give some kind of reward to people who are doing what they are supposed to do.
Then set up reward systems to encourage good behavior. When you add these 3 components together it gets results. It is never as simple as this and yet it Is as simple to start with this, if you get what I am saying.
So what I am saying is this: Riot is setting the groundwork for a good foundation. What they are starting to do is exactly as it is usually drawn up. We need the punishment system to start to get the game on the right and successful path.