Even though Fassbender's character is arguably the best thing about the last two films, the writers still messed up by making that the case, IMO. In at least the first three films (Alien, Aliens and Alien 3), the android was only a side character (albeit an important one). They weren't called Android, Androids and Android 3, after all. These last two films, however, seemed to me to fundamentally change the focus so that the aliens became more of a side character, instead. I don't think that anyone ever argued that the original films would've been better if they had been more about the androids and less about the aliens.
I understand that it's hard to make things fresh, but Cameron had that very problem by following up Alien and he hit it out of the park by delivering something that felt fresh but kept the focus on the aliens, while arguably fleshing out the franchise universe better than even the original did. Another really creative writer and director might've done that for the franchise again. Maybe Cameron getting the rights to The Terminator back will make him nostalgic and lead him to try his hand again at the Alien franchise afterward. That's been my dream for a long, long time. I have more skepticism nowadays, since Avatar wasn't very good, but at least that had a very clear plot, which would be nice for the Alien franchise to get back to, rather than these convoluted, pretentious plots that are hard to summarize, if even remember.