Let's say you have 1 year left to live. You have two things you want to do, X and Y, but X and Y take 1 year each to complete. It is the end result you want, but each result takes 1 year achieve, and you only have 1 year left to live. What can you do?

Well, if you have enough money, you can pay for someone else to work on X while you work on Y. In this way, you have been able to get 2 years worth of work done, in only 1 year. In effect, you doubled the number of years you had to spend on getting things done.

Spending money in exchange for someone else's work is a time multiplier on the one who spends the dollars. They get more done in less calendar time, i.e., because they effectively have more effort-time by converting their money to someone else's calendar time.

The entirety of my reasoning in predicated on one simple thing: an investor trades in their money for something of equal value, and the worker trades in their time for something of equal value.

This means, by definition, they are equal partners in the exchange, and hence must split the profits equally. It also means they each gained and lost equally, because they traded evenly.

If you do not agree with the foundational assumption I am making, point out the error in that, as all else necessarily follows.