As a scientist, you should understand the point of isolating the contribution of specific factors to a certain outcome. Sure, sensor is only one of them, but that doesn't preclude from looking at it in isolation.
Certainly. Say we identify a drug that completely inhibits a particular enzyme isoform. We could evaluate performance against isoform 1 in isolation and declare success. But there are three isoforms in every diseased cell, and thanks to the uninhibited activity of isoforms 2 and 3, the patient still dies. Consider a given factor in isolation, fine - as long as you realize that factor is one element of a whole system, and it's really the system performance that matters in the real world.
The problem is when people equate better sensor performance on certain metrics to better overall camera performance across the board. But honestly, when I read posts by Mikael/ankorwatt, Aglet, et al., it comes across that they believe that sensor DR is the only aspect of camera
performance that matters, and that the same it true for everyone who picks up a camera.
You keep touting this sales horn since forever and i cant really understand it, "what does X or Y matter when sales show that"
That's not really the reason. There are many aspects of camera
performance that can be considered. Sensor performance is certainly one of them, and it gets beaten like a dead horse in part because its easy to measure. How do you quantify AF performance in a standardized way, or ergonomics, or whether having a 14-24/2.8 is more important than having a TS-E 17mm, etc. Different aspects of performance are going to have different relative importance to different people. There's no such thing as "the best" camera, especially once cost is factored in.
Sales figures are a surrogate to discuss an overall comparison in the context of a generality. Obviously, everyone should make their own buying decision based on the factors that matter to them. But in aggregate, the fact that Canon is the market leader means that more people decided the features, cost, and 'intangibles' of Canon dSLRs made that 'the best' for them. So, if we say that Sony/Nikon has better sensor DR, but Canon sells more cameras, that suggests that, in aggregate, sensor DR is not a driving factor in the minds of the majority of buyers. Obviously, for some people it's the most important factor...but those people are in the minority.
You are under captivity of negativity
Well, 'agree to disagree' has been tried. Unfortunately, the result has usually been 'agree to be disagreeable'.