In an international capitalist context, if a nation keeps a capitalist economy it exposes itself to international competition. So any welfare program financed by the national economy harms the nation by makeing local companies less competitive.

A social democratie may therefore just go for little welfare things, and constantly need to defend its policy toward (justified) critics on international competitivity.

If the economy is organized in some way that doesn't comply with international competition, but is, for example, planified and state owned ; then it is not a "democratie" (in the eyes of capitalists).

Socialism, communism, and anarchism do not aim at establishing a political dictatorship. Even the "proletarian dictatorship" is supposed (in the theories) to be the power given to the workers collectively ; not to "the leader".

The problem with social-democratie is that it creates the conditions so all rights and protections given to workers are temporarily given to them so that they don't revolt, at times they could set a socialist society if they revolted instead. It is a shield to protect the interest of the richest.