Capitalism is dominant because it is the only model known to survive with stability long term over massive populations.

Gee I wonder why socialist countries you are thinking of just up and failed?! Just spontaneously happened, no external interference whatsoever, no siree!

Capitalism hasn't even survived with stability in the short term: it's yet to manage even a century without a catastrophic crisis.

Capitalism has instability built into its model because it generates inevitable class conflict that has to be resolved through violence. There is no such thing as a stable capitalist state.

They didn't have to recede to survive, they were fucking killed that's why they're not socialist anymore. Because they were all overthrown or sanctioned to hell or invaded.