And yet he gave us nothing in terms of what alternative economic would look like apart from a "a free association of workers" or something. Turns out it's a hard problem.

Too bad he couldn't predict what would happen in late-stage socialism (mass starvation and inequality)

>late stage capitalism

That period is defined as starting about 100 years ago, after WW1. 100 years later the "late stage" capitalism outlived communism in USSR and China.