By your definition, the spiritual thing automatically becomes material once it's testable.
Yes I suppose so. But isn't that how our knowledge has progressed? Natural phenomenon that were once deemed spritual or supernatural now have scientific explanations? (weather, fire, fertility etc. etc.)
I guess it is phenomenon which are claimed to be intrinsically spritual and therefore untestable regardless of technological levels that I was thinking of.
A better definition for this discussion to prove or disprove whether there is evidence for spiritual, material, metaphysical or whatever things is to list the qualities and properties that make up something material, physical, spiritual and metaphysical, and then see if we see anything with those properties and qualities within the universe.
Then I think it would be a good idea if you gave an example of the sort of thing you consider to be spiritual and what it is that makes spiritual rather than material.