LOL. What does one thing have to do with the other? Zonnie/Nadler were writing the previous Cable run and they're Hope fans. So with his death Marvel decided to give them a oneshot about that. That's it. That issue isn't a part of Extermination. Brisson wants to have Rachel being a hound again as a plot point for X-Force/Wi-Fi, all he replied on twitter when fans were upset about the Rachel thing was just "It's not over, I'll get to that soon, I wanted to leave a thread open for X-Force".
It was definetely in poor taste and I get the frustration. And she has also bonded with Rachel on the '90s and, more importantly, recently on X-Men Red. I just think it's very obvious that this isn't all about showing how Jean doesn't care about Rachel, but rather writers just not handling things very well, and we just have people who hate her using that mess as an excuse to bash Jean.