The Deadpool movies aren't part of the MCU and don't tie into the continuity (other than meta and tongue-in-cheek references), so it doesn't have to slot into the clusterfuck that is the current Disney-MCU storyline, direction, whatever. It ties into the X-Men franchise but loosely enough to be completely standalone and free to do whatever it wants. It is still Ryan Reynolds' playground, he brought in "his" writers, director, crew...
That being said, the second Deadpool movie already wasn't the best so I don't expect the third one to be much better.