This took place in Ohio, where the front license plate requirement was actually dropped recently in 2020.
For anyone wondering, the non-front-plate states are the "rugged 21" and are:
Alabama
Alaska
Arizona
Arkansas
Delaware
Florida
Georgia
Indiana
Kansas
Kentucky
Louisiana
Michigan
Mississippi
New Mexico
North Carolina
Ohio
Oklahoma
Pennsylvania
South Carolina
Tennessee
West Virginia
...But not regular Virginia. That's because everything is still illegal in Virginia. And luckily New Jersey drivers are also still required to have a front plate, so you can identify them coming and take evasive action.