Personally.. I just don't mind the direction which Weaver and Blomkamp wanna go in, and if we consider their statements... Nothing is being retconned. I don't understand why people are assuming that a diverging timeline automatically means it's a retcon. It just means we have more than one continuity, and that no matter which one we pick, it's all equally true and no one is invalidated. From what I've gathered, based on Weaver and Blomkamp's statements, Alien 3 and Resurrection still happened but elsewhere. I don't see this as a bad thing, I don't get why everyone else does.
To me, and this is how I see things, it just means we don't HAVE to follow a linear path. We have choices. So why is having a choice a bad thing? Someone please enlighten me.