No forgiveness necessary; you make a valid point. If one takes the long view, insofar as that's possible, one can focus on either the long-term overall or the shorter-term (relatively speaking) back-and-forth trends that take place within specific societies. I agree that there's an element of "backswing" taking place within information-age culture at the moment; the exclusivity of jargon creates language barriers that represent divisions between generations, races, cultures and income levels, etc.
It's my take that this movement is representative of the tendency towards "tribe-mindedness" inherent in human beings. But, as you note, there are significant survival advantages to cultural interchange. These advantages tend to only show up on the long-term, though, and are marked by significant obstructions in the short-term. When two tribes (however they happen to be demarcated) meet for the first time, there's almost always a violent clash. Then there's a period of subjugation, with forced unequal integration; then a period of segregation, with rigid resentful isolationism. But eventually, these social pressures tend to ease up as new generations are brought up in an integrated environment, and eventually people tend towards a state of re-integration where previously rigid cultural distinctions become more fluid.
Like I said, this is how I interpret cultural movement over the long-term. People who have been forcefully integrated into a society where they are disempowered are, quite naturally, going to want to break away from that society and form isolated groups where they don't have to suffer under disempowerment any more. This can be described as a necessary early stage in the formation of a functional cultural identity. But models of cultural formation indicate that once this stage is passed, social groups will gravitate towards a state of interaction and cooperation with other groups.
This makes sense on an evolutionary scale, too; while resources are extremely limited and unevenly distributed, it's better to fight off competitors and hoard as much for yourself as you can, because you stand a better chance of surviving that way. But when resources become more plentiful and more evenly distributed, fighting and hoarding become more costly than they are beneficial, and cooperative sharing becomes more advantageous. (Obviously, I'm only talking about first-world nations here; there are plenty of places in the world where these conditions don't apply yet, and I have to admit I'm kind of glad I don't live there, because, as you said, I wouldn't have the luxury of debating these things philosophically while I was engaged in a struggle to survive.)