It seems to me that there are at least two good reasons that cause Sorensen to "pay more in Social Security taxes than for federal taxes."
He pays more in Social Security taxes because it is expected that he will need more in Social Security payments to meet his needs when he retires. I paid my Social Security taxes (which increased over the years) and I'm pleased that I have the income from Social Security now.
He pays less in federal taxes because "Reaganomics" advocates less tax revenue than is required to meet the debts of the nation.
I didn't vote for Proposition 13, but the home protection feature is as reasonable as "homesteading," which didn't get so much adverse publicity.