Utopian dreams of democratic central planning have never materialised.
That's because they never existed. Democratic central planning is a contradiction in terms. It's so fundamental, I don't want to bother explaining it.
Democracy does not result in "market economies" or vice versa. That too is so fundamental, I don't want to explain it.
People seem to think it's fine to use terms such as democracy as if two people voting in a population of 1.3 billion constitutes a democracy for the 1.3 billion. It doesn't. If you're going to use terms so willy-nilly, then define them first. Qualify them until the cows come home because that's what you'll need to do. It won't guarantee you won't look like a false propagandist, though.