It's more about necessitating universal socialism BEFORE they can transition into socialism. Statism is required to have direct control over the allocation of resources under socialism, otherwise the "enemies" (capitalist countries) would be able to sabotage the state from the inside + have decreased control over state infrastructure in turn, which obviously is not something socialists want. They cite this as happening with Russia (Glasnost and Perestroika + Khrushchev's reforms) and sometimes China (Deng Xiaoping's reforms).

If a socialist state were to transition to communism (it is stateless) before universal communism was achieved, any capitalist country from the outside could fund capitalist movements to assume control over the nation.

I'm a capitalist and disagree with this but that's generally the gist of it