Yes, about half-way though I saw where this was going. A bottom-up positivist attempt to redefine "values" has (as you say Heidegger) precedent, but is usually steps along the way to defining what philosophers mean by value (so distinguishing universaliable/simpliciter kinds of "good/bad")

Those kinds of "facts" have utility. It's useful to know such "states of mind facts" as "That dog will bite you if it doesn't like you". But that's not real values. IIRC this is the difference between cognitive and non-cognitive value theories, but I forget now why that difference matters.