Social security is not an investment, it is welfare. Although you pay into it proportional to your income, you may not receive accordingly, there is a cap as to what you will get out of it. Illegal immigrants can get social security without work credit (there is a long list of exceptions for immigrants that do not need work credit, recently including the men that evaded their draft in Ukraine but also anyone that had to endure spousal abuse, Haitians, Cubans, etc etc), disabilities, being trafficked - so that includes pretty much anyone except for Canadians.
If you are earning $10,000 or more per year for 20 years, you receive 70 to 80 percent of the Social Security benefits paid for a full work life. Note that you do not have to “work”, being unemployed, Bethelites and special pioneers are often on some kind of “disability”, earning a stipend together with odd jobs, unemployment and state assistance, all counts because from your unemployment/income there is a withholding which at the end of the year (at tax time) is technically negative, it is considered “paying into” and making you eligible for payout.
Yes, those of us paying $1500/month in social security taxes, we are expected to receive $600/month out of it and the others are subsidized by us to the tune of $500-550/month. The thing you don’t have and what people may be confused about is 401k or pensions, you earn that on your own, it has a yield of approx. 180% if you work from a reasonable age (so if you pay into it now for 40 years, you can live very well for the other 40-60 years). In comparison, Social Security will have a net negative investment rate for the average person (you will never get out what you pay in)