I am well aware. I was just telling you one reason they do it. I'm sure you've noticed by now that movie writers and studios aren't exactly the most creative/willing to take risks when it comes to major franchises like this.
Actually...they did. Just not permanently.
Pretty sure they were trying to stay as far away from Origins as possible. For obvious reasons. Not the least of which was that the aforementioned Deadpool was wildly popular, and had just taken a massive shit all over it.