There is really no evidence that Stroud is going to be a great DE. He's a 3-technique DT, long in the tooth, and overpaid to be trying to reset his career at a new position.
Frankly, his career at this point is following the same trajectory as Langston Walker's did last year. Walker has plenty of "he was good there for a game", "I like him", "he'll be fine" comments to try and ease the doubts, but in the end he was simply discarded by the side of the road.