The "value" = "intrinsic value" = "amount of labour socially necessary" you're talking about has nothing at all to do with market value.
Very good, I made that point 11 pages ago.
Marx made it 150 years ago.
You made the point that Marx's labor theory of value is economically meaningless?
Economics is a social science, yes. It purports to study the system of production and distribution of life's necessities in society. As such, Marx's theory of labor value is of great value (not market value

) to the understanding of economics. He stripped away the facade that is the money form and exposed the true essence of the commodity, the basic unit of trade in an economy.
It can be ignored, indeed it has been actively suppressed. But it is still there, underlying the whole economic system. His theory accurately explains the capitalist system of production.
There are two sources of value in an economy. Nature and labor. It is only by labor that nature is improved upon. Value added.
Labor has been exploited in one form or another for most of human history.
In human's less developed stage slavery was the method.
As humans developed, that form of exploitation lost favor and a new system of exploitation developed in the form of feudalism. Now people were free to work the land for themselves but only after they had produced what was required from the owners of the land. Well, some people were set free anyway.
Eventually that lost favor and a new form of labor exploitation developed, capitalism.
^ this is what Marx's theory makes evident.
It is only labor that improves upon nature and adds value to society in the form of a commodity. Without labor your economic system is irrelevant, it doesn't exist.
You two are nothing but a couple of monkeys slinging mud in all directions trying to discredit something that is fundamentally true.