Speaking as someone who is Eastern European of descent, having in part grown up here, that just doesn't capture the division. It's like talking about the similarity between German and American culture culture. I mean, sure, to an external observer there is a great deal of similarity, and in the modern period there is a great deal of shared history, but that really doesn't capture very important differences in how stories are told and what ultimate cultural values (see e.g. attitudes toward sex and violence, or attitudes toward legal immigration and immigrants).
Poland, for example, is not very much like Romania, which is not very much like the Albania. There are different languages, alphabets, a different historical relationships with the Turks, the Muslim faith, and Catholicism.
Speaking as someone who actually lives here... I agree. I mean, I never said that there are no differences, in fact I explicitly said that Eastern European culture shouldn't be treated as monolith.
I'm just saying that overall, Eastern/Central European culture has a somewhat different flavor compared to that of Western Europe and while a lot of Witcher is sort of generic, Middle Ages/Renaissance period-inspired fantasy, a lot of it can be viewed as a love-letter to local folk beliefs and old myths, with an aim to likely showcase that we do indeed have our own myths (lol, despite the fact that Poland has been always torn between East and West, but always harbored an ambition to be viewed as Western Country, to a point that in schools we learn more about Greek/Roman myths more than our own) and our own cultural identity.
That is NOT to say that people should confuse gritty, bloody tone of Witcher games to "how things were and are all across Eastern Europe". In fact, I'm quite annoyed by that.
There were a lot of structural and social problems endemic in communism, and the optimistic post-revolutionary period was something that (depending on the country we're talking about) wore off pretty quickly. The kind of cynicism about human nature that's inherent in the Witcher - the books, in part, though Geralt is an almost comical "SJW" in there, and the games a lot more - is a reflection of the kind of cynicism you see in post-communist dictatorships.
Oh it wore off suuuper-quickly. I grew up in 90-ties in Poland and can attest that in terms of mood or attitude of people at that time things were almost schizophrenic. People finally began shaking their cynicism and pessimism off after joining EU, when things actually began looking fairly well. It's not like cynicism or complaining is over though, but I'd say that after two more decades (as well as 2010 Presidential Jet disaster in Katyn) it kinda re-contextualized itself - now, at least Poland, is divided into carefully optimistic (though somewhat frustrated) and somewhat progressive half that just tries to live decent life and one that is very right-wing, fairly nationalistic, protective of traditions and wary of change.
If we take that into account, I think some of CDPRs choices with narrative may not just reflect Sapkowski's observations on 90-ties, but are (more or less subtle) jabs into rhetoric spun by our far-right populist politicians and activists (and some of them are craaaaaaazy. Tea Party crazy I'd say. What's worse, our center-right government - inept as it was in many regards - has now lost its steam and those delightful delinquents are now marching for power....)
But to me the cultural values - and the ways that they're different - are so apparent in the Witcher, and in the (translated) books.
It's a bit like how Bioware games are so very Canadian in a lot of ways, and seem more progressive to Americans just because of our cross-border differences in what social issues are important and in how they are seen.
Well, like you said, Geralt sometimes almost passes as near-comical SJW in Witcher, which is why I sometimes feel Bioware's DA is closer in spirit to Sapkowski's books than Witcher games are, lol.