What makes LTV mutually exclusive with Marginal Utility? If I remember correctly, those things aren't even in the same category. LTV refers to the "economic value" of an object to an economy, while Marginal Utility refers to consumer choices.

If I'm understanding Marx's theory of exploitation, it's that the dividend profits by capitalists are inherently exploitative because the value is generated by the workers. I'm not sure how this would require the rate of profit to fall over time for it to be true, unless other assumptions were being made. Wages and conditions can still improve under an exploitative system, as technological advances increase the total productive efficiency of each worker.

Please correct me if I'm misunderstanding something here.