I strongly disagree with the premise that there’s a “wrong” way to play retro games.

I understand your sentiment here and you are right too. What I think is, that the wording on this title here is misunderstood. Emulating (old) games without Shaders is not faithful or accurate in the looks. It looks "vastly" different and thus means it looks "wrong". I interpret the "wrong" in the title as "not faithful", instead as "bad", like this: You're Probably Emulating Retro Games Not Faithful (you need CRT Shaders for the oldschool look)