This is something that's easily said/asked. I'm not Neil and I don't work for SI, but just to give you an idea of the scale of the ME -
It contains 2-3 million lines of code. That code allows it to calculate (it's a disservice to call it a giant calculator, but that's how I think of it) several decisions (I can't remember exactly how many) per second for the 22 players on the pitch and a full 90 minute match to play out and not only generate realistic scorelines, but also fairly realistic detailed stats (and it'll be different if you compare the EPL to the VNN, to other countries, IRL and FM) over that 90 mins. And trust me, SI do compare match stats (team and player stats) from multiple leagues around the world to what's generated in-game. No other football game (to my knowledge) has done that - simulate a realistic 90 mins. You don't just throw that away.
Over the years, sections of the ME, both small and large were overhauled or re-written. I don't know where SI stands on this, to make it clear, but there isn't another ME that's close to it. I'm not saying it's perfect and there aren't areas that can be improved, because there certainly are, but (again, IMO) you build on something that's good - you don't get rid of it.