Foundation of all human conflict: "You're picking on me!"/"No, you're picking on me!"
Toddlers play the "you started it game" over and over.
And countries tend to play it whenever they go to war.
You're always the good guy, the other guy is always the bad guy.
Truth is usually that both sides have some jerks, which draws in average people against said jerks on each side.
Edition Wars aren't much different. Fanbois and haters both have problems accepting the validity of someone else's position.
This attitude is actually a big part of the problem. It's completly false.
People are not equivalent, people don't argue simply to argue, and where there is a conflict, somebody usually did 'start it', and while there is rarely black and white distinctions, in actual fact it is often the case that one side is in the right, and the other side is in the wrong.
There are endless real life examples of this, unfortunatly mentioning any of them as an exmaple is likely to result in trouble. It would also be unfair to asociate this debate with RL debates relating to actual scientific fact.
However, it's also completly unfair to pretend that this is simply a tribalist squabble between interchangable partisans. The edition wars are caused and perpetuated by the hostility towards 4e, and that hostility is not rational, resonable, or constructive. But it's as toxic there as it is there to pretend that everyone is just arguing for the sake of arguing, and that fallacy does a lot to obscure the issues and, ironically, make empty partisanship that much more attractive.
People who hate 4e keep this cycle going. Yes other people then retaliate and the two sides argue a bunch, and the 'pro-4e' other side of the debate is far from flawless, but it's incorrect to suggest that this is some kind of purely subjective space where people argue purely for the sake of arguing.