Okay so first off, I used that A>C>B thing because it's how people like to downplay Tobirama in saying he is weaker than Darui, when in fact that isn't the case. In case I didn't make it clear, Tobirama lost to 20 elite ninja, all of which are at least jonin level. I'm not saying that's a bad thing, quite the opposite. But the point that I'm trying to make is Tobirama is stronger than what people make him out to be:; specifically speaking, he may have almost died taking on gin and kin at the same time, but that doesn't mean he is weaker than Darui who was actually able to beat gin and kin. That's what I meant and been pointing out.

Now, for you saying "feats are just feats" well that is certainly true when we consider the character itself. Every character in fiction has the potential to do better. But we use feat scaling when we pit two characters against each other when in reality it would be impossible for them to meet each other in the story due to lore. Going to the earlier example, Tobirama and Darui didn't interact with each other and would be impossible to meet each other due to Tobirama being dead for two generations before Darui was even born. So to settle a hypothetical fight between them, there is no other choice but to use feats that they both accomplished (and also compare them to similar fights or opponents they fought) to come up with a conclusive winner.

Again, I'm not trying to settle any "who would win" this time. I'm just trying to give Tobirama the credit he deserves and let people know how strong he actually is because people tend to think he is one of the weakest of the kage.

edit: also, the fight examples you gave all have specific reasons for why they lost. But for Tobirama against the kinkaku force and against the kin and gin brothers, there wasn't really a stated reason to how and why he lost which is what makes it such a frustrating case since it was clearly shown how powerful Tobirama was in the war and yet was beaten by two ninjas who obviously should not have been able to keep up with his speed and technique.