I like how the author intermingles assault rifle with assault weapon. An "assault weapon" is not an assault rifle,, author is either ignorant or dishonest.
"Assault rifle" has a definition: a rapid-fire, magazine-fed automatic rifle designed for infantry use. It has a select fire switch, typically single fire, three round burst, and full auto.
"Assault weapon" has no standard definition, it varies by jurisdiction. Typically, it comes down to "it looks scary". All are single fire but may include such features as a detachable magazine, a pistol grip, a barrel shroud, and/or a flash suppressor.
PoPo is not selling machine guns to the public, they are selling legal-to-own firearms that anyone who can pass a background check can buy from a gun store.