He was a rookie and showed some rookie flashes, but his technique and savvy were obviously raw. That said, he was enough of a disruptor (as was Barmore) that it helped mask Judon's decline. (last year's DL still was susceptible/exploitable to the run, they were just a better pass rushing unit as a whole)
As I've said elsewhere, I dont think he's an all-pro, but he's shown all the tools to be a solid contributor (and maybe more). He still is slower to recognize misdirection plays (all the rage these days) which is why he's often a step late and gets those damned horse collar tackle penalties.
That's mental/teachable, but the unknown is whether or not he can make the adjustment solely, he's not being taught/reinforced effectively, or he is one of those guys that's always going to need a star beside him to take the pressure off to allow him to maximize his skills.
I am definitely not in the "he sucks and needs to be purged" camp like some here. I remain optimistic he is another piece that doesn't need an upgrade position wise like so many OTHER parts of this Patriots team and those dollars and draft picks can be used elsewhere.