Boutte is being replaced by Brown, not so much Doubs, as Doubs can play X, Y or Z
By my thinking if Doubs is playing Y or Z or running those routes, you can have Boutte run the deep outside route with Brown on the other side - putting our 3 best WRs on the field at the same time, and likely confounding Ds who may double team Brown, while Doubs runs a route across the middle and Boutte goes deep
Boutte doesn't get the same separation as Brown does, but is still a helpful asset assuming we keep him.