I think this goes a LONG way towards explaining the difference of opinion that floats around. To me, 4e is very much an evolutionary change for 3e. Virtually all the systems in 4e come from 3e. There are very few elements in 4e that didn't appear in almost exactly that form, at some point in 3e. Skills work the same, combat is largely the same, although saving throws are an obvious change, as well as NAD's. Most of the task resolution systems are ported over largely unchanged from 3e to 4e.
Whereas I look at 2e to 3e and see that as truly revolutionary. Virtually none of the systems in 3e appear in 2e. Feats are a completely new addition. The skill system is completely different. Combat is changed in a thousand different ways - 5 foot grid, AOO's, out of turn actions (something that is greatly increased in 4e), on and on. Heck, even the meaning of the base stats are entirely different and on a different scale. A 16 Str in 3e and 4e means exactly the same thing. And it's completely different from what a 16 Str means in AD&D (1e or 2e). There's a reason that your 18 Str character got converted to like a 22 or 24 Str in 3e using the WOTC conversion rules.
So, yeah, I think this, right here, gets right to the heart of the different ways of seeing the games. After all, flavour wise, 3e and 1e are a lot closer together. I'll totally cop to that. The cosmology, alignments, the races, monsters, etc. are pretty much pulled directly forward. And 4e's flavour changes are significant and probably rightly called revolutionary rather than evolutionary.
It's all about what you see as "the game". To me, the flavour bits are usually an afterthought because I almost always run homebrew settings. Great Wheel cosmology? Never used it. Alignment? Well, used it and it caused me WAY too many headaches. Tolkien Races? Haven't had a pure Tolkien group in about twenty-five years. Whenever the Dragonlance player's book came out which had Minotaurs in it. That would have been about the last time I saw a group with all standard races.
So, yeah, it's all about perception.