I think the Rangers just wanted to move on from Stepan because they thought he was going to decline soon and didn't want to have to deal with his NTC.
I don't think Gorton would say something like that to the media. So of course he's going to say something like "it gives us some cap space to make a move."
That's like...one of things that all GMs say whenever a big trade like this happens. They won't say their actual motives to the camera. Gorton won't tell the media "Yes, we traded Stepan because he's slow as hell and we don't want to deal with his NTC when it's likely that he declines even further."
No. GMs are going to say the obvious things in interviews.