Eh, you can blame me for that.
When Lauren's patch was coming out I put together the rough story board for it.
At the time there were no other male characters at the school, and I had mistakenly thought that Will always intended to make Matt an antagonist. I really needed a antagonist for Lauren to run against, and since NTR in the game was not a game over but a consequence of the MC making bad choices. Well, it all just fit together so well.
When Will looked it over he liked the idea enough to change his original plans and move forward with the concept.
If I had to do it all over again, I probably would still keep Matt as Ryan's rival just because of how negatively people react to him. I don't think Matt will ever reach Eric levels of hatred but it's nice to dream.