Some people go through printers quickly and put them out for yard sales or even in the trash. People also let friends use printers. Someone could inadvertently get criminally charged for something they didn't do.
I am concerned that the explosion in electronic communication will create problems for people unknowingly traced and possibly falsely accused or suspected.
In this day and age, even being suspected of something can be ruinous. They might not be able to lock you up in jail, but it will become impossible to transact any kind of business to live.
The authorities supposedly could match typewritten documents to a particular typewriter via high magnification. The conviction for perjury of Alger Hiss* was based in part through a match up of typewritten documents.
*Alger Hiss was a prominent government figure. A man named Whittaker Chambers accused Hiss of being a communist spy during the Communist witch hunt era. Hiss denied, under oath, being a spy and ever knowing Chambers, Chambers said they were close friends and that he lived in their home. It came down to either Hiss or Chambers was blatantly lying. Hiss' story had a lot of holes in it. It was too long to charge Hiss with espionage, but he was charged with perjury (lying under oath), convicted, and sent to prison. He and his wife proclaimed his innocence until they died many years later. Liberals felt it was a frame up. Richard Nixon, who was in Congress at the time, found a lot of evidence implicating Hiss and that propelled him to fame. Liberals hated Nixon ever since. Today, general agreement is that Hiss was indeed guilty of perjury.