Is it fair for the Social Security Bureau to pay endowment insurance in this way?

If the state stipulates that it will not be refunded, the value of your personal account will be given to you at retirement age.

Unlike commercial insurance, social security is a state-owned welfare policy. This is mandatory, so you must agree to pay, not pay, anyway, this is the rule.

Don't say anything that is fair and unfair to the country. Fair and unfair, that's all.

You don't call the insured, the company pays you social security, and you only pay a small part.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.