Things like https://en.wikipedia.org/wiki/Goodhart%27s_law happen regardless of political regime or economical system. In different situations they take different forms: in capitalism, companies try to maximize (short-term) (perceived) shareholder value; in socialism, they try to maximize the favor of the ruling party. In capitalism, your values are important proportionally to how much money you have; in socialism proportionally to how good political connections you have. In capitalism, sometimes people starve to death; in socialism, sometimes people starve to death.
The world has many problems, but lack of military dictatorships controlled by a communist party is not one of them.
Of course, unless you meant "actually, true socialism has never been tried yet". In which case, sure, as a rule of thumb, imaginary countries do not suffer from real problems (unless the plot demands it).