Well to be honest introversion typically does not mean reclusive or completely isolationist personality and for the most part almost none of us is entirely like that. There is a certain amount of social interaction that we all thrive on. When the article or whatever states that when a person is cut off from socialization it is implying complete isolation which I dont' think many, if any of us actually experience.

Another aspect that may not be being considered here is that the interaction we receive online although not exactly the same level of socialization is still socializing. I am going to assume when someone speaks of a human being cut off from social activity it includes any and all of it. Don't forget you still get a bit of social interaction here, in chat and in other online environments, since you are receiving feedback and replies from other people.

I don't disagree with the statement that we are social creatures. I myself am pretty reserved and introverted, but I have to admit myself that if there were no people to talk to or interact with irl of online I'd probably become severely depressed too.