It’s an economic theory and therefore more to be understood as a model on how economics work.
The natural sciences have a hard core. The theory of gravity depends on how matter interacts in an objective, physical framework. Economic theories basically describe human interaction which are based on psychology and sociology. Therefore they depend on the societal context they are made in.
If you understand them as models that are tools on how to understand the world, they become more useful in political analysis (I know we are in a meme community here, but everything is politics and so on and so on…).
I do subscribe to many conclusions the labour theory of value and especially Marx came to. But I want y’all to remember that the theory is a mere tool for understanding and not a sacred, holy theory.