The was a string out here about 4 years ago when Jeff Luhnow left the Cards for the Astros and was spied on by the Cardinals in what might have been the dirtiest bit of cheating in baseball history. At the time the Astros had been terrible for years and the Cards riding high. A number of Card supporters wondered why they would bother spying on such a mess of an organization.
All these years latter it would seem the Cards may have let one of the brighter baseball minds get away. That coupled with the Cubs ascending while they have declined - the teeth seem to be coming out. I think they see an increasingly mediocre organization that had been run very well for 30 years and are worried about it.
They have never really been on the short end of the Cubs but they have been for 4 years now. That looks like something that becomes more permanent and it may be that sense is starting to seep into the fanbase. Cubs have more money and with Epstein may finally be the better organization. If Cards suddenly become a 75 to 82 win organization for any length of time - it could become a real problem.
It would represent the biggest change in baseball dynamics since the Red Sox replaced the Yankees and Braves as baseballs best organization 15 years ago.
IMO it has already happened and baseball has entered the phase where NYY/Bos/Cubs/Dodgers will be permanent fixtures in the playoffs for 10 or more years. Places like STL/SF/CLE/DET that have been competitive need to be very careful not to fall behind. I think they have fallen off the pace and if it doesn't get fixed soon they may be mediocre for some time. Think Seattle - sort of competitive but no threat.
That is why where Harper and Machado end up may be so important. Machado to Yanks and Harper to Cubs or Dodgers would only cement my point of view.