The problem with optimising exclusively for oneself is that you definitionally optimise at the expense of others. Gaps are easily widened, and your balancing idea falls apart when the scales are tipped from the start.
It is not as simple as "my profit" vs. "others' expense". The elegance of the invisible hand theory is that it also accounts for the cases where others' expense is my expense and others' benefit is my benefit just as well as the others.
The scales sure can be tipped on the individual level, but you are only considering the "one individual vs. one individual" case. Many cliques of extreme power have been taken down by the weaker majority, which is also one of the processes contributing to the collapse of monopolies.
No, it isn't, which is why I added "definitionally". Let's say we have a limited resource, X, that is beneficial to hold, and it is more beneficial to hold more of it. As it is limited, acquiring necessarily means depriving another of it. Assuming one has the means to acquire more without impacting oneself negatively, in which situation (taking optimising for oneself as a maxim) you not seek to acquire more?
Precisely. As of such, those with increased capacity for access will deprive access to others. No balance of care forms. Your recommended ethic is what Kant wished to address with his categorical imperative.
Of course this is a unifaceted way of posing a problem: it's a model, given we're dealing with philosophical ideas. I should hope that I needn't provide examples for the model, given the state of the world at present won't let you swing a cat without hitting one.
You need not. It's evident to any reader that some models can take more into account without overloading, including the "access" variable you introduced ex post facto.
What I suggested is an instance of Kant's categorical imperative: "Act by the maxim whereby you can at once will that it should become a universal law." The maxim in this case being "optimize for your own benefit."
This is very funny. Let's take a different approach.
You are in a situation where you have a particular benefit. You may choose to share part of this benefit with another individual, who can be said to be deprived without it. This individual lacks the capacity to gain the benefit by their own means. Said individual shall be a permanent stranger: you will never again meet, your choice here being without future consequence as a result. Sharing your benefit diminishes it, but does not lose it.
The scales sure can be tipped on the individual level, but you are only considering the "one individual vs. one individual" case. Many cliques of extreme power have been taken down by the weaker majority, which is also one of the processes contributing to the collapse of monopolies.