>First of all, I'm going to need you to define capitalism

Capitalism is an economic system, and all economic systems are defined by a set of rules. The rules of capitalism are: You can't steal or harm another person's private property, and you can't break a contract. This is in contrast to, for instance, Chinese communism under Mao, which had a rule that stated you can't own farmland and that all farmland would be owned by the community. This led to a scarcity of food, because no one had an incentive to produce much food, because any food they produced would be split up equally among the community. There was actually a small community who agreed to privatise their farmland such that the owners of the land got to keep all the food that they produced. Basically, they reinvented capitalism by creating private property. That town ended up producing so much food that China eventually adopted capitalism as their main economic system after Mao died, and the rest was history.

>Automation has reduced scarcity more than any industrial paradigm in history. Automation is possible both with and without capitalism.

Things don't just magically happen. Individuals have to make things happen. Individuals are guided my incentives. So you can't just say "industrial paradigm" like it's a magic wand. It doesn't mean anything. If there's an incentive to be more efficient, then sure, there will be automation. But if there is no incentive, there will not be automation. So when you say "automation is possible with and without capitalism", you need to be specific. Which exact economic systems have an incentive to create automation? Certainly not communism where things are collectively owned as we saw in Maoist China.

>Capitalism means the primacy of capital and capital holders as the decision engine of the economy - i.e., capital holders control the means of production and hold sway over the rules of the game

By that definition, you could argue that the chinese farmers which collectively owned their community farm were all "capital holders". So that's not a very good definition. Your definition also doesn't allow us to make predictions about how individuals would behave in such a system, which is the goal of any science. This is why in economics, economic systems are defined in terms of rules. It's way less ambiguous and allows economists to make predictions. Did you take microeconomics in college? It's a really good course.

>But capitalism has literally negative interest in eliminating scarcity...

And yet despite all that waste, global poverty has never been lower: https://ourworldindata.org/grapher/share-of-population-living-in-extreme-poverty-cost-of-basic-needs?country=~OWID_WRL

So clearly there's more to the story for each of your points. Food spoils, logistics is expensive, etc etc.

>and keep supply low by supporting restrictive zoning laws that forbid the construction of multi-family residences like apartments and condos.

When the government creates new rules and regulations that restrict the free market, blame the government, not capitalism. Also it's weird you're blaming companies on zoning restriction when the most famous NIMBY city is San Francisco and the people who live there.

>it sounds like capitalism is the very source of most of the scarcity in both of these cases.

"Source". Scarcity is the default. Things don't exist unless individuals make them exist. So the fact that there's so much food as there is right now is proof that capitalism has reduced scarcity. And again, global poverty has been dropping significantly.

>Then explain why insulin costs $5 to make and $300 to buy, smart guy.

Because the FDA makes it very expensive to do business. You can create insulin at home, but you'd go to jail if you tried to sell it to anyone without approval from the FDA. I could also say "explain why coffee cups are so cheap compared to insulin, smart guy." In general, when there's one-off expensive things it's usually caused by the government

>Capitalism is not "everything our economy makes".

Right, capitalism is private property and contracts. Those two simple rules happen to incentivise individuals to go out into the world and create everything the economy makes. But in the context of comparing different economic systems, it's pretty fair to say the capitalism is everything our economy makes as a shorthand.

>Capitalism is not "freedom"

Right, because capitalism is simply the enforcement of private property rights and contracts. But compared to other economic systems I'd argue it's one of the most free economic systems possible.

>Capitalism is not even "free markets"

Well, you can't have free markets if you don't have private property and contracts, so it sort of is.