I've found it's usually a relation in sorts to the underdogs, in some way or another: a vengeance against the status quo, a sort of angsty reactance against it, or a desire to simply do the usual thing and signal yourself as "alternative". That's all the hipsterism is: a kind of counterculture. The author of this post is basically saying in the subtext "You're simply living off the scavenged technology of corporations and these computers aren't built for what you see in them. You are a stupid 20-something with false nostalgia," which I could argue is just a different sort of social signaling.
There is some truth in both sides of the Thinkpad culture argument. Thinkpads have excellent Linux support, ludicrously bad color gamut, questionable build quality generation-to-generation, but are always serviceable if not attractive. If the MacBook is the AR-15, the ThinkPad is the AK-47.