Rex is doing a good job with what he has to work with. Revis goes down, D hasn't missed a beat. We've gotten great contributions from our young WRs. What Rex cannot overcome is a turnover prone QB that ranges from great to horrible, often within a quarter.
We traded up to #5 in the draft to get a franchise QB that could torch bad pass Ds. Instead, we got a QB that can put up numbers on a bad pass D, but still makes enough mistakes to the point where the decent numbers don't even matter. You're OK with mediocre QB play, you've made that well known. Some of us, however, are not.