Thanks for this, I like the pragmatic view that those with economic power select those who obtain political power. I certainly don't think they're independent. The economic system influences the political system for sure, but categorically/formally we're still talking about two distinct systems, otherwise we wouldn't be talking about a separate political structure

I see, I think there are a couple things to clarify. Causally, you can view it as the political system of decision-making determines the economic system, so keeping capitalism is a political decision made through a political system such as democracy or theocracy with downstream political consequences, e.g. property has high capital value, which affects citizens.

You may also be conflating decisions that carry a political quality with decisions made by a political system. Or conflating systems that carry political qualities such as economic systems and education systems with political systems proper, which are system for instituting decisions that govern societies. For example, the market may "decide" that asbestos is the best insulation, however, the market does not set political policy about insulation. It is up to the political system (e.g. democratic parliament or dictator) to decide whether or not to pass policy about limiting asbestos insulation, not capitalism. This distinction is also present in your own argument. Like you said, the market (capitalism) doesn't create and enforce property law, it's the state (political system) that creates the law and is responsible for enforcing it.

-EDIT- Okay I think I see the semantic disagreement. What others are emphasizing is that the economy is political in nature and therefore it is a political system. What I understand for the term "Political System" is more narrow to be more narrowly "system of government". I certainly agree that the economy is political in nature. And honestly, I'm not married to my definition of political system. What I cared more about is drawing the distinction between "system of government" and "systems that are political in nature". The only reason why I'd disagree is that by the latter definition, any system of social structure such as religions, education systems, human transportation systems, communication systems, language systems etc. Are also political systems because they're political in nature. So the term "political system" may be too broad as to be useful.