Not necessarily true, i know entry level engineers earning well above $100k in the Bay Area who are barely getting by because they are paying $5-$6/mo in rent alone which is post-tax.
my total monthly expenses are roughly 3500/month so I am able to save almost 50% of my post tax income.
and the USD salaries would put you in the very very top earners of the population. Though sourcing enough devs here would be tricky for anything beyond 10 people if you actually wanted to outsource to NZ.