Men’s buttons are on the right to make it easy to do up with one hand for right-handed people.
When buttons were invented, only the wealthy wore them. Wealthy women had maids who would do the buttons up for them, and so the buttons are on the left so that they are easier for someone facing you to do up.
It makes women’s blouses more expensive to dry clean, because they can’t be pressed on the same machine that does men’s shirts without breaking the buttons.
Damn you patriarchy.
Too bad that they can’t make a female version of that machine. After all, women are a rare minority that only make up half of all human