This was the most likely outcome of the formula that McBeane sold to the Pegulas, and which the Pegulas may or may not have knowingly endorsed.
They brought in a first-time GM and a first-time coach, and proceeded to rid the team of talent. It is not a huge surprise, then, that at the first sign of trouble, the team loses all confidence in itself and its leaders (the coach and front office) and hides under the blanket.
The formula was flawed from the very beginning and many of us here saw it coming. If you want to shed the team of talent to rebuild the "culture," you'd better have Superbowl-winning credibility in your coaches and front office to fall back on (i.e., Coughlin in Jax). Conversely, if you're starting from scratch at HC and GM or lack winning credibility there, your best bet is to stockpile talent and make sure your coaches and their schemes know how to maximize it (i.e., L.A. Rams).
The Pegulas are very nice people. They're wonderful Buffalo citizens. They're also the most clueless owners in professional sports. And as BADOL points out, they're not going to tolerate this regime for too long - I'm willing to bet that McBeane promised them that a competitive team would be fielded this season despite the aggressive personnel moves. Welp so much for that, so it's Strike One against the McBeane regime. They'll get a Strike Two. Strike Three is "You're fired."
Always Be Closing.