It is ridiculous that someone would dispute this.
Our OC is average to below average.
To be concerned about an average to below average coordinator going against one of the best coordinators out there (the SF DC Fangio) should be reasonable.
Here is how bad our OC is right now, for the past several weeks after every game we had several threads talking about how they felt that our OC (or coaching staff) was going "vanilla" to avoid showing their hands for the playoffs. So our OC was so bad that people were actually inventing imaginary reasons for why we were so bad.
Anyone defending him probably isn't smart enough to figure it out so there is likely no reason to waste bothering trying to explain it to them. But the rest of us know it. He wasn't "vanilla", he was just mediocre to over-matched.
Now we are going into the biggest game in recent memory, and we are saddled with this same Weak Link. In fact the only reason that people did not realize this sooner is that Wilson would often run around scrambling and make some crazy play here or there. But without that factor suddenly our OC cannot do anything. Wilson's improvising was masking the truth that Bevell was simply not a great or even good OC.
Now Wilson looks slower, he isn't running as much and worse, his own accuracy is plummeting. I think he might be hurt but we probably will never find out for a while. Either way, if Wilson is not doing his SuperMan imitation out there then Bevell isn't going to get any results in the passing game.
Bevell isn't producing up to snuff, that should not be in dispute at all. We need him to earn his paycheck because right now he isn't.