Car insurance is expensive because cars are both risky and highly destructive. Hence, making a market for them involves high prices.
Regardless of what you think of insurance companies, there’s just no way around this - you could nationalize car insurance and it would still either be really expensive, either on the policy level or else born by taxes.
The U.S is different in that car insurance has to cover medical expenses for others when you are at fault, combined with the risk of driving quite frankly being higher in the U.S. With medical costs being extremely high in the U.S, prices follow that fact.