...
I wouldn't argue that. It doesn't necessarily follow that if Nazism probably only comes to power in a world with a successful Russian revolution that Bolshevism or even the socialist movement in general is a mistake. It may be that the 20th century could well have been worse, for example in higher total deaths from infant and child mortality in a Russia and China that never underwent revolutions, not to mention in terms of the array of social reforms and civil rights protections that might not have developed to the same extent.
Still, the broad drift of industrial development is striking irrespective of the mode of production. Looking at Russia today - as a higher middle income nation - and comparing it to other late developing nations that never went through a socialist revolution, it's hard to see it being much poorer or less egalitarian than if Lenin had never made it back to Russia in October, and if the Provisional Government stayed in power. In retrospect, the industrial revolution is a more important force in history (and with it, the disappearance of the peasantry), as part of the development of the forces of production, than any number of temporary Marxist regimes.
Parenthetically, I do think these sorts of counterfactuals have some modest use, and that the left should not leave them entirely to the right, who tends to monopolize the field of counter-history.