But my point is not about vanguardism per se, but what vanguardism does in alignment with whatever ideology is relevant. With collectivism in its various forms it leads to extreme oppression up to and including mass slaughter as the vanguard tries to force people to align with a prescriptive, unnatural, i.e. fundamentally wrong ideology. A commonly accepted figure for the 20th Century is 100 million killed by their own socialist governments, I personally estimate (using very rough projections from those former worker's paradises where bodies have actually been counted at least somewhat) upwards of a quarter billion.

By contrast, the "ideology" of capitalism is much more aligned with human nature, it also sets up a system in which everyone is perforce required to minimally engage. Do some work, get paid some money, buy some stuff, repeat. People are strongly encouraged to do more of all of those, but there are e.g. no block or village committees that watch for layabouts and deny them the ration coupons necessary to get food.

(Appropriately, with the 25th anniversary of Tiananmen Square today, just before then my roommates were a couple of grad students from the PRC, and one of the things they told me was that Deng's economic reforms had negated the ability of these committees to casually kill people. With a free market in food getting on their wrong side meant you paid more to eat, but not automatic death by starvation.)

And of course my other point is one you implicitly agree with: pure, "scientific" Marxism does not and cannot exist.