Prayer is only superstitious if there’s no God. No one can prove there’s no God, but plenty have come to a knowledge of God by reason alone. Atheism is a foolish stance because you say there is no God. Agnosticism is at least reasonable because you say you don’t know. If you don’t know then given the importance of the subject and what religions teach wouldn’t it be logical to act as if there was a God even if your unsure? Just to be on the safe side.
I make a vain attempt to prove the existence of God, the immortal soul, the proof of the catholic church being the one true church and how to get to heaven on my angels website in the section - inherit eternal life. The link is in my signature if you want to look.
The claim is flawed because it’s based on the presumption there is no God which can never be proved. It could ask is prayer superstitious and then seek to find the truth. But it doesn’t.