Statistics underestimate Watkins value. By stretching the field, and attracting the attention of each opponent's top corner, he has opened thing up for Woods and Kupp, as well as for Gurley. As he gets more in sync with Goff more success should follow.
The compensation for him is less than meets the eye. Gaines, although a steal in the 6th round, would have been a backup for the Rams. The value of the 2nd round draft choice is diminishing with each win.
Granted, they have only leased Watkins for one year, but even that has its advantages. The final year of Watkins rookie contract is a bargain. If the Rams resign him, they will have a deep threat for years to come. If he leaves and signs a big contract elsewhere, the Rams will get a compensatory pick, perhaps as high as a third rounder.