Just wait until wesker comes back somehow. Then things will get really heat up. There already gave revival hints in ucorps, both wesker and umbrella.
Honestly sometimes ı feel that the series could have been actually concluded permamently if re2's story was written in a way to return all surviving stars members as a way to take down both umbrella and wesker in the same game. They were both concluded separately then ucorps went ahead and somehow brought them back in the same game. I dislike that game and as a result, ı dislike re engine. Hope re4r will turn out better than previous re engine games regardless.
Umbrella Corps was developed in Unity Engine, an Engine that's technologically superior to RE Engine. That said, Umbrella Corps practically retconned Neo-Umbrella.