this is correct, the median household has a (positive!) net worth of ~$120k. you have to go down to the tenth percentile and below to find households that actually have negative net worths.
I find it really hard to believe that only the tenth percentile has more student debt than savings. Virtually everyone I know in the 20s, and many in their 30s with advanced degrees, all have more debt than savings.
that shouldn't be too surprising. the lower net worth buckets are made up disproportionately of younger people who a.) are still paying off student loans (if they took them), b.) have yet to reach their life peak income, and c.) haven't had as much time to accumulate savings. if you look at the breakdown by age on the page I linked, you'll see that median net worth increases almost monotonically by age bracket.
you might also consider that there is probably some sampling bias in your social circle. I'd guess it disproportionately consists of people who have advanced degrees, possibly from more expensive schools. as a counter-anecdote, most of my friends got STEM degrees at a state university. the ones who took out loans paid them off completely within two years of graduation.
As far as the median net worth, that's just someone most of the way through paying off their mortgage...