Dialectic can never be a science, you can’t apply the same methodology. Even when it’s material.
However it is philosophy, and if your searching for some material reality then it’s ontology.
Science too is a product of ontology, it’s a methodology created for this exact purpose and wich can be studied in this field.
Saying physical properties are social abstractions sounds to me like social constructivism, which is epistemology, again philosophy.
Social sciences can be soft science precisely when they are not dialectic and rely on the methodology of science.
And to be clear, soft science is just a science that is based on a hard science, in which we don’t have enough work done to explain every emergent properties using fundamental properties of matter.
Psychoanalysis is an outdated philosophical theory, so indeed just a scam now.
Labour theory of value puts value on goods for the sole purpose of trading and explaining trades. Both LTV and STV does.
Marx’s use of LVT is to criticize how Capitalism leads to exploitation. But although the specifics differ SVT could still be used to raise the same critiques.