I see two sides to this argument.
On one hand, he is right: deconstruction is not a critique, and more people need to learn the difference.
On the other hand, when people present a deconstruction as critique, what they mean is that "your magic circle is too obvious, it no longer suspends my disbelief, I see what you are doing".
Imagine if he was talking about stage magic: "Knowing how the illusion works does not detract from prestige" - that is obviously false.