Is it an apology or admission of being wrong? No, no, of course not. He says he still holds the same opinion, but as he has never nor will ever actually play a video game, he shouldn't have said so. In other words, he still thinks no video game could ever be art. He just was wrong to say that out loud.
I don't think his original thesis is in the slightest bit defensible. How hard would it have been to say "Ok, video games can be art, I just don't appreciate that form of art"?