What you're describing is a form of technocracy (rule by a class of dedicated scholars). It has been tried occasionally, but it is essentially the same thing as any non-Democratic rule: the technocrats do what is best for themselves, and using their knowledge and expertise, are able to invent convincing reasons on why that is supposedly best for the country as well.

This is especially true when the "science" they are supposed to study is economics, a notorious pseudo-science whose real purpose is to act as justificationa for policies desired by whoever is paying the research.

There is no way to ensure that rulers align with the people unless the people have a say in who rules. Scientific authorities have a long history of being negative even for their own fields ("physics advances one funeral at a time"), and that doesn't change when they are given power over an entire country.