1. As far as I know there is no keyboard layout (especially for English), that has an em-dash key, they all have hyphen/minus. 2. As far as I know, only MS Wor

1. As far as I know there is no keyboard layout (especially for English), that has an em-dash key, they all have hyphen/minus. 2. As far as I know, only MS Word will auto-correct the use of a hyphen to an em-dash. In all other instances - ESPECIALLY text boxes on web - if the user uses the hyphen-space-hypen pattern then it will posted like that verbatim. So either a lot of people are drafting their posts in Word first, and then pasting into Reddit/elsewhere. Or... It it looks/quacks/walks like a duck and all that.