When I first read his blog post I added an item to my todo list to write a lengthy reply. I never did, and now I think it is time to do so — but it will be in Polish, as it is mostly Polish people who might be interested.
I think Michał has an extreme view of both the United States (which is not the paradise he paints it to be) and Poland (which isn't nearly as bad as he describes). As someone who has lived both in Poland and the US, I came to opposite conclusions: I would much rather live in Poland. I could live anywhere (I don't have the visa problem like he did), but my choice is to live in Poland.
I am puzzled by his extremely negative experiences. People all around me get paid good money for doing extremely interesting work. The money isn't necessarily the same as in the Silicon Valley, but it goes a long way here: living in Poland (even in the largest cities) still isn't as expensive as in Western Europe. All in all, as a young person entering adult life, you will be much better off here than in the US, assuming you are a highly-skilled professional (which he is the extreme definition of!).
I also find it disconcerting that he begins with a historical note, describing Poland's struggle for independence, and then follows with a description of how he basically said "I don't care" and moved out. It is worth considering what happens to countries where most people make a similar decision.
But most importantly, I don't understand Michał's negative viewpoint. My experiences have been very different: my standard of living here in Poland is really good. I don't want to describe what I dislike about the US, especially since Michał does not seem to even consider criticism ("no matter how smug the critics are"), so I'll just say that it can look very, very different from a different person's point of view.