Context would help. This type of statement would be within a company that is going to reduce the budget on the scientific department. Arguing against that, would be the "the importance of scientific *** cannot be overvalued. Overvalued would be a financial term. And as others stated, this is an exaggeration. In literature it's called a Hyperbole.
Outside of a business setting, the statement should be ...the word "overstated" instead of overvalued, but context isn't clear.
Meaning: Scientific study is very important.