I understand your stance, but it is hard to say where the line stops. Should a running back not get credit for a fumble if the play was blocked incorrectly and someone comes free and strips him? He never looked to his right because the OLB was supposed to be doubled by the TE/OT, but guess what, the got through anyway and stripped him...should the RB not get credit for the fumble?
I just think in a team game, the QB has to take the hit...like in basketball when the PG throw the ball for the cutter...but the cutter doesn't keep going to the rim, who gets the turnover? The PG, even when the cutter stops the cut. Same thing for QB when a WR runs a wrong pattern, drops the ball, cuts the route short when he shouldn't have, who gets credit for the INT as a results? The QB. In the film room, they may not get credit, but on ESPN, they do.
Oh yeah, there are all kinds of stats that create a distorted picture, thats why I don't trust stats (entirely). I cite them like everybody else because lets face it, if you like sports we live in a stats world, but IMO the way we keep stats is antiquated and there needs to be a stats revolution, particularly in football.
Baseball, to its credit, has experienced a stats revolution with saber-metrics. Most of us don't use saber-metrics because its complicated, but at least its there for the baseball diehards who want to get a more accurate picture of whats happening on the field and individual performance. Football has nothing like it and IMO its desperately needed. I'm sure behind the scenes there are smart organizations that don't use official stats, but look deeper at cause & effect.
That said, there are still some things that are black and white, even if its flawed and it doesn't tell the whole story. For example, if you are a RB and you take the handoff cleanly, its your responsibility to tuck it away, squeeze the life out of the SOB, and don't put it on the ground, even if some dipshit misses a block and lets you get blind-sided, you have to anticipate big hits that you might not see coming, and hold that ball for dear life.
But yes, you are correct, sometimes when a fumble occurs there is more than one guilty party, the RB takes part of the blame because its his responsibility to keep the ball off the ground, but that doesn't mean he's solely responsible, other people can be culpable too.