Eh, honestly, Sapkowski is just a Polish guy, who doesn't care much for videogames. He has a formal, direct way of speaking which comes out as critical or negative when translating into English. There are bitter undertones to the English article, that I don't sense at all when reading the original. All he says about games and CDPR is very respectful, and praises them multiple times but he just doesn't throw empty praise the way english speakers would do. He didn't play Witcher games, and is familiar with "graphic materials" only - which could be screenshots, or trailers or snippets of the game.
What he does though is draw a clear line between his work, and CDPR's adaptation. He isn't critical of their work, he just considers it to be its own thing. A new work based on his characters, not a continuation of it - and as someone who read all the books - he is absolutely right.