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."
Unless you are studying an a priori science, textbook examples are pedagogical simplifications. Yes, the cost of environmental pollution is paid neither by factories nor their customers, yet both suffer the consequences, and as such are not "uninvolved" with the third party, as the definition goes.
How is the environment, which is directly of concern to the primary economic sector, and to the entire economic enterprise in the long run, an externality?
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.
I agree with the author that questions of ethics are social optimization problems.
> We must balance optimizing for oneself with optimizing for others
Yet if each person would optimize for themself, then the balancing is automatically taken care of. The invisible hand is even more free and dexterous on the social scale than the economic.
> the belief in the magical power of the free market always to serve the public good has no theoretical basis. In fact, our current climate crisis is a demonstrated market failure.
The power of the free market is at least as theoretically and empirically sound as the climate crisis.
I was searching recently for a photograph of Arthur Rimbaud in his later years, and noticed that already Google Images was flooded with AI-generated stuff from websites that do not require marking it as such. Authentic material will soon be much harder to find for people who don't know the sources.
Whenever I want to put something down, I open the browser on my phone, type in the address bar, then hit <CR>. Later I synch them along with the other tabs when I have access to the desktop. This routine developed totally unintentionally and has been somehow more productive than all the fancy notetaking apps I'd used. Maybe it's something about the claustrophobically tiny input slot that makes me want to widen it as much as possible. Another bonus is that when I later get to format the long string of text that is synched (as you can see I don't believe in the paragraph when writing on my phone), I get loads of additional ideas.
In my experience making music, specially the more experimental kind, is therapeutic for the musician.