The main use case for local emulators is unit testing. Maybe even some integration testing, especially for stuff like VPC setup that often can't be done without global side effects.
Security for dev accounts is not a big deal, just give each developer an individual account and set up billing alerts.
> Security for dev accounts is not a big deal, just give each developer an individual account and set up billing alerts.
If your only focus is spending, yes.
Otherwise, a "not a big deal" dev account can quickly become the door to your whole org for hackers