Why are arcanists left handed?

[Kazrah]

I'm left eye dominant and right-handed. I hold a bow with my left hand and draw the bow with my right. I can't shoot left handed, tried and failed lol. Maybe I'm a mutant.

An eyepatch on your left eye would probably be a better alternative.

As for the original question, I'd think it's because Arcanists rely on glyphs, which are more on the artistic side of math, and the left hand is controlled by the right half of the brain, which is usually associated with art and other creative factors.