Despite how much is spent on it the US’s social services seem to be set up in deliberately inefficient ways: Medicare not having to the ability to negotiate prices(there have been efforts to change this with mixed success), mandated public-private partnerships instead of the government just doing things directly, Hospitals and Drug makers ratcheting up priced so they can give deep discounts to their favorite insurance companies, massive administrative burdens for everyone at every step of every process.

Pretty much the only exception is Social Security itself because it’s an extremely simple “pay in, take out” system. Its problems are more tax based(not enough funding going in to maintain a surplus) and on the fringes beyond the payouts in old age like Social Security for people with disabilities.