We are not old, there is a reason the generation is said (in stats and polls) to be less professional than prior generations when entering the workforce
I remember hearing that people used it as a way to signal that they were too busy, too on the go, too important to use proper punctuation..it was an obnoxious c suite trend as long as I can remember. Like you're always trying to signal that you were doing all of your comms from your cell phone between meetings/travelling. Given this article's tone and content I would say that what the author is trying to emulate or convey , maybe subconciously.
Interesting. I am a millennial and I never did this, nor did I have any friends that did. But I know m nephews deliberately turn off the auto edit in there iphones.