Tax is charged both federal and state in California. And 160k hits a 28% tax rate at the state level. Combined it's about 35% in taxes (about 56k, let's call it 60k).
Rent + Utilities + Transport can easily put you at 4000/mo (48k, let's call it 50k).
160k - 60k - 50k = 50k
Now if he is also contributing to his 401k (18k), that leaves him with 32k (or roughly 2600/mo)
IF he has to feed a wife & 2 kids, pay for school, clothing, etc. It can get a bit tight.
160k/year is not an outrageous sum in California. Even less if living in New York (where there is also municipal tax).