[WS:] This is what I do not like about economics, Marxist or classical - or for that matter theology. It tends to answer empirical questions with definitional tautologies i.e. make things true or false by definition and deduction rather than empirical investigation.
As I see it, how much compensation owners of capital receive is an empirical question, and the answers vary by different social settings. In the US, for example, employees who manage capital owned by others (e.g.stock brokers, corporate executives, etc) receive much higher compensation than the actual owners of that capital (e.g. retirees or savers). Your theory does not seem to be able to explain those empirical variations.
-- Wojtek
"An anarchist is a neoliberal without money."