I agree with your record position as well. And yes, the politics/personality/history of a player absolutely factor into whether he will be added to a particular roster. The NFL is absolutely business/entertainment, so the fact CK has an appreciable group of fans boycotting a product will absolutely weigh-in to the personnel decision.
My issue with these CK articles is the claim he is this silver bullet for any bad organization based on statistics alone. Add him to the roster, and the team will improve. There is nothing to support that position. Nothing. And this 'talent' argument, for or against adding him, is an empty word, not an empirical/factual component of the argument. CK can have a lovely singing voice, but that does not make him an improvement in very different schemes as a QB. Talented at what - a QB role without definition? Brady was not viewed as talented at the combine in those measurables, yet somehow he worked well for the Pats. I wouldn't want Brady running a read-option offense either. So under this amorphous talent claim, stripped of fundamentals on fitness for particular systems, is Brady not a 'talented' QB? His stats are awesome, but is he going to achieve comparable results in a read-option system with an emphasis on running? Not remotely.
QBs like Brady also will pull wins from losing scenarios. I have watched CK quite a bit, but do not see him as that type of QB day in, day out. I know Jim Harbaugh loved him, protests or not, and they ran a very specific type of offense. Harbaugh left, the scheme changed, and CK was benched. What to make of the lack of confidence from Harbaugh's successors is anyone's guess (there were not protests for all of that, but it may suggest that Harbaugh had to coach him excessively in order to get him to that level and Harbaugh is a great coach). The Niners were and are a disaster.
Does CK have the abilities to play backup if he is committed to learning the particular offense? Sure. Will he sign on to that role? I have no idea. Is a backup worth a PR nightmare? Probably not. Is CK the type of superstar QB that teams will morph an entire offensive scheme to accommodate? No. Has he elevated a team's play to heights unimaginable by his abilities alone? No. Are stats influencd by the talent on the team? Yes. How many number 1 receivers were added to the Niners roster with CK? Quite a few. Is there a guarantee in another system, meaning any of the systems outside the Niners under Harbaugh, he would achieve better results than these other lousy QBs listed above? Absolutely not. The only universe that reasoning works is Madden NFL, where his subjective numbers say how good or bad he works elsewhere.
By the logic of these articles, Ochocinco was a 'talented' receiver and should have 1,000 receiving yards for the Pats given his 'talent' and Brady as QB. Apparently worked to fit in, good guy and ultimately a disaster - 15 rec/231 yds/1 TD. There was no PR cost for him in adding him, but he didn't fit the Pats system, despite physical abilities and a desire to play for the coach. Corey Dillon, in contrast, worked with tremendous physical abilities and a role that fit those abilities.
I cannot claim to love the CK saga enough to do a team-by-team breakdown on skill sets required and comparative measurables of current QB and CK in order to determine if he is even better than the current player in that role and would ultimately prove to be a step up from what is currently there. Having said that, I haven't read that analysis from anyone else touting the amorphous 'talent' argument in support of the blackball theory either. Just stats from the Niners, which are just that. Teams in the end want wins, not stats. If CK cannot do that, then what good is he, and why should he be starting anywhere, regardless of his politics?