I won't argue with the private ownership of the means of production. You can see the need of this in legal monopolies like power generation where the barrier to entry is too high to produce competitiveness or it's infeasible/uneconomic to do so. Not to buck your assertion, because it's true, but it is most certainly not exclusive to capitalism. Take Communist China mid-20th century, it works the same way there as well. Jung Chang in Wild Swans describes this pretty adequately. Communism has a hard time dealing with both individuality and incentive. Marx even has admitted how his ideas are flawed and that his true vision would require a strong economy to enable. His assertion is that you have to have stable markets to enact a state-less society. I want to note, again, that capitalism is not a political theory, it is a product of trade and specialization. There are very few instances in history where a society has attempted to advert them. Now, you certainly have historic societies that placed merchants at the bottom of the social structure and probably for good reason. Am I fan of laissez faire capitalism and the selfish espouses from those like Ayn Rand? No. But do I think that an equitable capitalist system with a democratic governance is likely the best form we have experienced to date? Probably. What you describe is corporatism.
True capitalism: I own an apple orchard. I want to trade my apples for good from other people who specialize in their crafts/production. It would be inefficient for me to attempt to trade my apples for everything. A market is then created where I can exchange my apples with others for capital, and then use my capital to purchase other goods. Excess is used to fund my well being (risk), for savings or to invest in my community in the good of society.
Corporatism: I own an apple orchard. I want to trade my apples for goods. The market is created. Instead of using the surplus to assist with my community, I use it to step into a new market. Now I am participating in two markets under an umbrella corporation (typically). I then continue to expand and gain market share. Enter monopoly laws, taxes, ect.
Regan convinced part of a generation (and those thereafter) that instead of supporting competition, we should support conglomeration in the form of trickle-down economics. The R's have followed suit ever since. They gaslight you with the stock market (it's doing so well!), but how much of that do you actually see? How much is rigged behind it?
I believe the problem is that you and I haven't ever participated in a fair economy. That's absolutely a problem. The beauty of capitalism is it gives you leverage where political ideologies tend to lack teeth, it's just that it was compromised long before we were born. Think about it, in a diversified, transparent market you would produce more change buying alternatives than picketing outside Target or Walmart. That option isn't totally gone, but it's so damn expensive you won't dare buy outside the big retailers.
My stepfather was a German immigrant. He called the United States goldene straßen. He was in WW2 as a German Navy officer. When the war was over, he bartered oranges with his mother for goods. Economics has to do with the distribution of the finite. Capital markets are a tool, akin to a gun, that can be used for good or ill. It doesn't espouse a ideology, though it absolutely lacks humanity. I like to think of it as meritocracy (in theory, not as it's practiced today) where it doesn't matter who you are, what you look like... we're just interested in what you bring to the table to benefit society, and in turn, you will benefit as well. It's not something to use to subjugate people.
If you haven't read about it already (you seem extremely astute), I would recommend looking up Distributism. Here's a small snippet from Wikipedia:
Distributism views
laissez-faire capitalism and
state socialism as equally flawed and exploitative, due to their extreme concentration of ownership. Instead, it favours small independent craftsmen and producers; or, if that is not possible, economic mechanisms such as
cooperatives and member-owned
mutual organisations, as well as
small to medium enterprises and vigorous
anti-trust laws to restrain or eliminate overweening economic power
I absolutely recognize where you're coming from. I've spent a lot of time thinking and researching about it, to be honest. If you really want to think about the future, well, it's communism. Sooner or later we will depopulate into more regional communities again, but this time aided (hopefully) by micro-production like 3D printing and AI.
Absolute power corrupts absolutely, it doesn't require a capitalist system just bad actors.