Social democracy does not fix every problem communism claims to because it preserves capitalism. Social democracy, but without capitalism is no longer social democracy. That is socialism. Believe it or not, communists are pro-socialism.
All of the Scandinavian social democracies that are supposedly the gold standard are former colonial powers. Colonial powers extract wealth from their colonies to the detriment of the indigenous inhabitants of the colony. This is referred to as primitive accumulation and is a direct precursor to capitalism. These nations built their wealth through colonialism and continue to maintain wealth through neocolonialism. This is really only unheard of or controversial if you have your head in the ground. Look up the WTO and the IMF and how they fuck over the global south at the benefit of wealthy nations if you’re interested in more information (spoilers: you’re not)
Where are your sources that all communists are fascists? Are the communists in the Philippines fighting their fascist government also fascists? What about in India? The list goes on. You’ll find that neither of these groups of communists are particularly fond of China by the way.