I've talked to many people who struggle with that in Korea. Especially foreigners married into a Korean family. It's already hard for the younger generation of Koreans to deal with the stubborn older generation who expects respect because of the age. That's why many woman do not want to visit their elders anymore during Chuseok and Seollal, they just can't deal with those old ajeossis.

What I've learned, you can't change people. On the off-chance you can make them change their minds, it's usually because they've come to the conclusion themselves. It requires a lot of patience, discussions, etc to open their minds to a different way of thinking... probably only worth doing so if those are people you interact with often.

I'm lucky to be in academia, with a boss who accepts when I tell him he's wrong. In industry, you can almost never tell your boss he's wrong in front of others. You need to let him think he's had the idea by himself.

Well, not really useful advice, you probably already know all of this~~