Jim's always had aspirations that far outstripped his reach and a bit of an ego to say the fucking least - as well as an aggressive urge to pander politically, and a level of self-righteousness that tends to undercut him in about a thousand different ways. In and of themselves, all of these traits are ones that can potentially demarcate lolcowdom, but they are not, by themselves, generally lolcow-worthy.
Something very specific in Jim's life exacerbates all of his flaws, inflating them from being his personal failings to being something we all come here to laugh at. That very specific thing happens to be Jim's social circle - something so utterly dominated by Lolcows that it would make Kengle jealous. It's this social circle - and the need to ultimately bend the knee to it - that is directly responsible for so many of Jim's multitudinous issues. The overpowering bulk of shit we make fun of him for now is a direct consequence of this social circle, which mandates that he behave in certain ways at certain times, believe certain things, and, of course, embrace the hypocrisy, arrogance, and partisanship that has, ultimately, turned him further and further into a laughingstock. Jim's problems are deep-seated, much more so than most realize, but he has done himself no favors by surrounding himself with the people he does.
When you look back on Jim's content, it's not hard to see transparencies between him and Bob Chipman, in that both of them followed a similar path, with the fundamental difference being that Jim was, for the most part, successful, whereas Bob was not. We can tell, however, from his current behavior, that this success has brought with it an arsenal of new problems, and the very nature of his social circle ensures he'll never have the chance to escape it.
Great for us, but kind of shit for him.