Thank you for the replies. I will probably use barrier=fence/wall for area features that are usually fenced and the area most likely would not change over time. You can still add tags like fence_type to the area feature and I am focusing more on adding fence at all than adding every posible detail of it, like color. Sometimes there are ruins or leftovers of wall that can be crossed because it is very low or fence that has hole and in that case a line feature is definitely better, because I can just make a gap.