From a pure business standpoint it was a dumb move on the Mets part. They had him under control for two more years. After that they could have decided if he was worth being paid as an elite pitcher. And I don't buy the argument that well if they piss him off now he will definitely leave after two years. Really, have you been paying attention, free agents over 30 have been sitting on the shelf all winter.
Also if they make the best offer after two years I doubt he would turn it down for spite.
As far as him being the best pitcher in baseball, last year he was. An historic year. Right up there with Seaver 1969, Gooden 1985 and Guidry 1978. He was smart to parley that into this contract. But before that he was above average not elite.
So my take, great for deGrom, good for him.
Dumb for the Mets