It's pretty understood around baseball, at least as far as I can tell, that Sandy Alderson, his front office, management and ownership all see eye to eye on not trading these guys, be it Zack Wheeler, Rafael Montero, Syndergaard, or even Jacob deGrom.
This approach, at least for now, will kill any potential for a blockbuster deal. It's why talks for Troy Tulowitzki, Carlos Gonzalez, Jose Bautista and others probably never even got started. The fact is, until Alderson gets a few of these guys to the big leagues, they succeed and are still earning the league minimum, it's going to be difficult to pull off big-time trades.
For instance, the Orioles and Rockies both asked the Cardinals for RHP Shelby Miller in talks about their top shortstops. In the Mets world, Miller is Wheeler. The Mets are going to need extra pitchers like this to make that big of a move, and they clearly feel the way to do that is to hold on to this crop as tightly as they can.