That's because the Witcher 2 actually has meaning and representation of the polish culture since it represents the polish entertainment industry and one of their most famed authors, Andrzej Sapkowski. MattPat only did it to have a video to defend a critical opinion that lacks basis and for the sake of the constantly growing Undertale fanbase to give him some views and likes (he would've done the same thing to Five Nights at Freddy's, had Scott managed to make FNAF stay relevant)

But Matpat mostly did it just for the youtube money and attention.