All communist regimes are dictatorships, by design.

That's why.

The amount of non-communists dictatorships are simply dwarfed by the spread of communism in the past 100 years. But you can find some, like Chile, Iran, etc...

And yes, it includes Ukraine, a country caught in civil war for 9 years, after a coup.

Or Canada, where Trudeau seize emergency powers unconstitutionally, and used private corporations to seize assets without due process, etc... (a.k.a. fascism, which, like communism, is just a variant of socialism)