Marxist thinkers spent an inordinate amount of time and effort trying to explain away the myriads of ways in which actual Communist revolutions didn't happen in the way he predicted.
I am thankfully not a "Marxist thinker," and thus will not spend even a merely ordinate amount of time trying to defend this particular tangent. Marx's prescience in economics and sociology is not meaningfully altered by his academic descendants.
Well, you can read my longer comment downthread but 'nobody accused Marx of non-prescience' just isn't true. Marxists did! Pretty much right off the bat.
Whether or not various communist revolutions ultimately succeeded is a sideline topic from the general concept that workers in our modern era increasingly are treated as a commodity, and alienated from their product.
There's various ways to attempt to ameliorate this sort of situation through regulatory means without having an October Revolution. I'm talking about more basic things like European countries' vacation time granted for every full time employee, companies moving to a 4-day work week or 32 hour schedule, maternity leave written into law, workplace safety regulations (Marx probably would have loved the general concept of OSHA), etc.
It's not whether they succeeded, they simply didn't happen where he thought they would, the way he thought they would nor developed the way he thought they would. This was a real, well-recorded problem - after all, his work aspired to be a scientific theory, if the theory predicts things but they don't happen, you have a problem. Dealing with this problem is a pretty big part of the development Marxism, it's simply inaccurate to say nobody thought he wasn't prescient. Marxists had to account for his non-prescience and went at it with great energy. Here's one historical example of many:
