It's a wrong comparison. A high-level language is usually good enough for a desktop app because there's not much ongoing computation happening. It's only input processing and small, infrequent updates to the view in response to the input (not to mention rendering of the DOM and low level input processing is done by the browser's C++ compiled code). A video game on the other hand has to do computations all the time at a very high frequency.
I agree that his tone could be better, but if this was really none of his fault (other than being at the wrong road at the wrong time), I could understand why he writes that way given the trouble it has caused him, significant time in prison, criminal record that he will never erase and debt that translated to US standards is way way higher than those 80k and it could end up way worse, too. Like of course, it's a tragedy what happened to the girl, I think a lot of people could relate to doing stupid things intoxicated when young, especially in countries where vodka consumption is high, I do not say that the tone is appropriate, but I could understand the place where he's coming from where the girls' irresponsible behaviour severely impacted his life, he is just quite angry. I wonder how many of the people in this comment section labeling him a killer (I don't say that you did) would speak with the same tone if they were put in the exact same situation given the lack of empathy with his situation.
What's your reasoning for saying he's probably not a great human being? Assuming what he says is true. If he had no way of seeing that coming, how is that different from blaming / judging a train driver in any way for someone's suicide or going as far to as to say they killed them.
[0] https://www.youtube.com/watch?v=LIvihYPq_mQ