I remember countless mystery movies, TV shows, comics and stories where a kidnapper or other extortionist of some sort sent a ransom note using letters or words cut from multiple newspapers and magazines to defeat handwriting analysis and prevent matching the quirks of individual typewriters. The jumble of different fonts made for a distinctive look.
I have no idea how common the tactic ever was in reality, but it’s got to be obsolete twice over. Laser printers pretty much wipe out the quirks of both handwriting and typewriter key alignment. And of course now you can send an anonymous email over a proxy, with no handwriting, fonts, or other signifiers other than those for the proxy itself.
Chalk up another trope made obsolete by technology.