It is incredibly hard to separate three things, perceptually, before even having a discussion with anybody about these topics, so I rarely try.

1. Marx and -- various political-economic thinkers who came after him inspired by him -- who were analysts of capitalism and modern society. Maybe also dabbling in prescriptive aspects -- but a lot less than laymen would think. Just full on boring economics or political philosophy concerned with analyzing the present, not describing any future.

2. Eastern bloc & Maoist "Marxist-Leninism", Stalinism, or whatever which became official state ideology in eastern bloc countries with simplifications of some of the above along with a series of rationalizations for the "way things were" in the USSR and related countries. Usually mangling some form of #1 to do that.

3. Various Marxist political action/groups/parties/sects which merged varying aspects of #1 and #2 along with whatever else, in various combinations and permutations, to intervene in politics at either an activist level or in political parties, or armed groups etc.

Especially people who grew up in the eastern bloc definitely perceive I think a lot more correspondence between #1 and #2 than I'd personally say is valid. A whole educational industry was built around it there for the purpose of ideological legitimation of some Really Bad Stuff. With some of that leaking into the west, too.

And I don't feel it's really a "no true Scotsman" type of statement to say that either. Marx himself had little to say about the future, and just a lot to say about the present (which is still our present). What #2 said about themselves doesn't bear much resemblance to #1 because it wasn't actually the concern of Marx or many of the thinkers who came after. They were critics of capitalism, not prophets attempting to come up with recipes to be used as justification by Slavic autocrats for crimes against humanity...

Hm, being born in a stalinist country I definitely encountered more of the Stalinisit interpretations and ideology and they are definitely religion like.

But I also did met various other marxists and I did read some of Marx books, or rather some pages.

And I do remember him speaking of the utopian future. And also the part where he thinks, concentration camps for the enemies of the proletariat (everyone who does not want to have his property taken) will likely be necessary.

So gulags would not be a Stalin invention then.

(I think I read that in some of the letter exchanges with Engels, will look up)

In general, marxists ideas have been tried in many places, east, west, north and south and they all turned out in a dictatorship as far as I am aware.

My standard question would be to ask, what would you do different, then all the previous experiements?

I think they're just trying to inform you that you're painting with a broader brush than you might realize.

There are lots of flavors of Marxism out there, the one you're describing is often called "Orthodox Marxism" or the closely related "Marxism-Leninism".

It's now considered pretty outdated, with most of Marxist thought having moved on to less rigid modes of conceptualizing history and geopolitics, like Western Marxism (Frankfurt School), Autonomist Marxism, Eco-Marxism, Libertarian Marxism, Structural Marxism, etc.

There is a reason that "leftist infighting" is a century-old meme. Leftism is fundamentally a political movement grounded in moral philosophy, but since moral philosophy is an unsolved and likely unsolvable field, fractionalism is guaranteed.

>It's now considered pretty outdated, with most of Marxist thought having moved on to less rigid modes of conceptualizing history and geopolitics, like Western Marxism (Frankfurt School), Autonomist Marxism, Eco-Marxism, Libertarian Marxism, Structural Marxism, etc.

I think that's not true. It is incorrect to compare the practice of Marxism-Leninism, and it's philosophy formed with such practice, with purely imaginary pink-glass-self-reflection fantasy.

Let them seize power in somewhat large country and hold it for at least a couple of decades - and then say how these movements are "less rigid". Or compare the voiced fantasies with Lenin's pre-revolutionary fantasies (remembering that they were practical enough to seize power and push it's philosophy on half of the planet), if you really want to show the difference between them and outdating of the latter.