I think a big part of that is that Rangers fans are seeing the player, while other teams' fans are pretending to do the same. Exhibit A--look at the post just before yours. That person lists 5 reasons why they don't want ADA. Only one of them is 100% valid (Seattle expansion). Another is pure speculation (looking for a big contract) and the other three are either YEARS out of date or pure BS (the character concerns, the defensive play, and the "probable" production in Anaheim--in my experience players are what they are. They don't "produce a ton more" or a ton less in a different setting. Everyone thought Nash would double his production in NY as well...nope, he was the same old Nash. There might be a small impact, but not "cut the production in half" level impact).
But again, I don't want to trade ADA. I want to see if he or Fox or Nils can play the left as effectively, because after this year, the left side of the D is going to be VERY young/raw.