Alvarez supposedly on the way as the Mets starting catcher for years to come may have been why the Mets went with James McCann for four years and $40.6 million instead of Realmuto for five and $115.5 million in the 2000-01 free agent offseason. I would bet that if Steve Cohen could borrow Doc Brown's Delorean and go back to that winter, the Mets would have signed Realmuto.
On a similar vein, the Red Sox could have had Cole Hamels for a package centered on Blake Swihart.