You simultaneously disprove and prove his point all in one post.
The post author never said he didn't like programming, but rather that he only does it during work hours. To respond that he should just quit and call him a petulant child for expressing discontent with negative personalities is the part that seems to prove his point.
edit: perhaps the confusion is that i can't see how you can enjoy something while judging others for pursuing it recreationally.
edit 2: "It’s probably unclear from my previous posts, but I’m a software engineer. I guess I don’t really talk about it much, since I don’t really like it that much."
if you want to be semantic yes, he isn't speaking of programming directly. but i cannot imagine someone who enjoys programming saying this. likewise, i don't see anything in the post that would lead me to believe he enjoys it.
To address your edit, I think it's purely inference to conclude that he either likes or does not like programming itself.
He can't believe there are people who program on the weekends, for fun.
He can't be bothered to learn anything new, or to even hear about concepts he doesn't understand.
He posts all the above on a public (until recently) blog, where his boss and all his coworkers can read it. What more do you need? If he has any interest in programming, he's doing a good job of covering it up with his endless complaints.
An actual statement from him, of course.