I hope you realize just how patronizing this thread is, despite your intentions.
I'm sorry I came across that way.
I think that you're correct in your presumption that there is more to changing systems than the objective qualities of those systems. However, your ascription of these difficulties to a generalized "fear of change" lacks substance and support. Here's a question: what evidence would lead you to believe that resistance to 4e is mostly "rational" (that is, based on the qualities of 4e vs. some other edition) vs. "fear based". Describe how one might discover the truth of the matter in this specific instance.
You're the only one to use the word "fear" in this thread. That's definitely not what I'm saying.
What I'm saying is that, when a change happens, there's a predictable sequence of events that occur. (And yes, this is a generalization that doesn't apply to everyone.) I see how people react to these things in my day job, and I see the same sorts of reactions in the threads here. So the edition wars look like a typical reaction to change to me... and so, I described that sequence of events in hopes that it would be interesting.
Is that patronizing? Maybe, maybe not, but it is human nature. Try this. Write "Pick one: 1 2 3 4" on a piece of paper, and show it to ten people. Most of them will pick 3. (You can show them the back of the paper afterwards. Write a suitably funny remark on the back, like "People who pick 3 make the best lovers," or "If you picked 3, you secretly prefer 3e.") We humans tend to be more predictable than we wish.
Anyway, I thought it might help to understand why people might not want to make a change... and generally, that resistance is
not about "fear of change." A person generally resists because he (or she) thinks the change will cause him to lose something he values. If he ends up accepting the change, it's typically because he discovers how to keep what he values in the new system.
For example, if Bob values his system mastery over 3e, and feels that 4e doesn't really support system mastery, then he might resist using 4e because he would lose that sense of mastery he values. Is that fear of change? Not really. It seems pretty rational to me.