My point is that systems theory is dialectical materialism. Marx didn't invent dialectical materialism. Legalists during the Zhou dynasty were already using dialectical materialism. It's the main reason why the state of Qin was able to steamroll the other Chinese polities and unify China despite starting out as an incredibly weak state because their main ideological competitors were a bunch of Confucians, Daoists, and Mohists, none of which espouse a dialectical and materialist framework (with the Mohists being neither dialectical or materialist).
Of course, their version of dialectical materialism is cruder than what Marx came up with. Systems theory is just the latest iteration of dialectical materialism. So why call Marx a dialectical materialist instead of retroactively calling him a systems theorist? Well, it goes back to what I said earlier about systems theory being an exercise in branding from anticommunist Western scientists. If anything, systems theory should be rebranded as dialectical materialism. Systems engineering should be renamed to dialectical engineering and so on.