I use the poor man’s emdash (two hyphens in a row) here and there as well. I guess I never noticed Reddit auto-formats them. I have been accused of being an AI on a few occasions. I guess this is a contributing factor to why that is.

Funny how Reddit technically formats it into the wrong glyph, though. Not like anyone but the most insufferable of pedants would notice and care, of course. I find it merely mildly amusing.