I'm wondering if you would define a higher than median US salary to be "surviving at best", as most CS PhD programs are at that amount plus health insurance. But certainly far from a FAANG salary, and I agree that there are disciplines usually with smaller programs that are "surviving at best."
That's not the correct comparison. Household income often includes two incomes, which is going to bring the value up. Your same link says the median earnings for a male individual is $61,417. Not significantly less, but this distinction is often important.
Median personal income is around $36k. [0] Annualized median earnings of the full-time employed are around $52k. [1] Households often have more multiple income earners.
Wikipedia notes, "The U.S. Census Bureau lists the annual real median personal income at $35,977 in 2019 with a base year of 2019 for all people over 15 years old.[3] The U.S. Census Bureau lists the annual real median earnings at $41,535 in 2020 for all workers with earnings[4] and lists the annual median earnings at $56,287 in 2020 for people who worked full-time, year round."
Of course there is also cost of living, and, quoting the AVETH survival guide (2012): "It is common in many departments to
reduce the amount of payment from 100 percent to 80 percent or 60 percent.
However, you are still expected to work full time. Make sure you know what
you are about to sign."
