this is definitely not true. the median US household has several thousand dollars in their checking account. they might be living paycheck-to-paycheck in the sense that their net cashflow is close to zero, but they don't have nothing in their bank account just before payday. you would have to go deep into the 20th percentile to find households like you describe.

https://www.thebalance.com/what-is-the-average-bank-account-...