Vlad,
zzzzzzzzzzzzzzzzzzzzzzzzzzzzzz oh, what. Science can't solve every question so in that case we must grit our teeth, suck on a victory V and...........use science!
........and that folks is scientism.
No.
First, that science cannot answer something tells you nothing about whether it ever will.
Second, when assertions are made about a supposed non-material then it’s for the claimant to come up with a method of his own to distinguish the claim from white noise etc - which is when you always disappear from the stage.
Third, no that isn’t scientism. Scientism is just putting undue weight on the methods and findings of science. What you’re thinking of is called “metaphysical naturalism” (or sometimes “philosophical naturalism”) which holds that the material is necessarily all there is. I’ve never come across anyone who subscribes to it (and nor I suspect have you) but either way they’re not the same thing at all.