Where did the rest of the Social Security fund go? [View all]

I have been paying into Social Security 1982-2025. The Soc Sec Admin very helpfully allowed me to get a complete download of all my contributions over that time which I set about analyzing.
I took the Standard and Poors 500 (SPX) index results over the same period and normalized those to a %-age increase (or decrease) year over year.
I Took my Soc Sec deductions from pay, plus the employer's contribution for each year and added the gain or loss from the previous year's contribution multiplied by the %-age difference for each successive year.
That gave me a final total of compounded contributions. Or in other words, the putative balance of my "account" if those SS tax deductions had been invested/managed wisely.
If I then amortize that over my current actuarial life expectancy remaining as a form of annuity, I get 6 times the amount PER MONTH for life than SSA is actually giving me.
At the current rate of payout, the value of my account will actually have INCREASED in value by the time I die, and it would take roughly until I'm 125 to exhaust my account.
I should have listened to all those advisors who said invest 10% of your income for life!
But what happened to all that money Soc Sec has been "guarding" for me all my life?
Why is my payout Soooooooo low?
Who is taking that money, and how?
Why, if they are giving me such a low payout, is the fund supposedly going to be out of money in 2030-something?