Us, Japan, EU, south whatever, there is simply not enough workforce to monitor everything, and these companies know it, you can't have a million supervising a million companies, they all have to do with the numbers these provide, and even if on inspection they find a flaw that will be discovered only after a trimester and then real action will take further months.
Besides, the major fuck up was not even over ftx.us but com, which was not US jurisdiction, in September 2021 was based in HK and then in the Bahamas, just like how CZ keeps binance.us clean so did SBF.
your learning finally.. but ontop of that regulators are not pro-active regulators. they do not actively audit companies to any schedule. instead they wait in their offices to receive grievance reports from customers or internal self reporting to then act.