I get where you're going, but the two players aren't even the least bit comparable. Chinn was a tweener that truly didn't fit anywhere because he wasn't big / strong enough to be a linebacker and wasn't good enough in coverage to play cover safety/nickel. Not sure what defense Washington ran last year, but Chinn is best suited for a 4-3 / 4-4 where he can strictly be an in the box safety. He did well with tackling last year according to his PFF grade, but he was still dogshit in coverage.
Even though Walker is a tweener also, it is much easier to find a spot on the field for him because of how good of a pass rusher he is.