The "deadly sin" of pride is arrogance, haughtiness, thinking of yourself as more important than others. It's not, like, being satisfied in your identity or accomplishments; that's contentment and it's definitely a virtue.
1,600 years of translation and linguistic drift (and probably not a little bit of puritanical nonsense) crossed some wires.
Also all of the "deadly sins" are made up bullcrap. Some of them are in the Bible, but some of them are just, like....some guy's opinion. Seriously, sadness was one at one point, so clearly he had never read the book of Lamentations.