For years when people frist started to get drivers lic. They were only good in one state.
Full reciprocity took years to come about same with vehicle registration.
Most people are not aware of that fact because it was some time ago.
The biggest scam about drivers licenses is that all those many years ago when they were first passed, they only applied to commercial drivers. Because it was widely known and accepted that you have a common law right to travel the public roads. Sadly 70+ years of propaganda have convinced many that you must ask permission from the government to travel.