Declaimer: I am not a native of a right-to-left language or culture. But I am not inexperienced in Arabic.
To support right-to-left languages and cultures, the user experience designs need to be careful to distinguish elements that truly are left / right of the page, versus those elements that are just left / right of the page because left-to-right languages and cultures expect them to be like that.
A classic example of the later point are navigation bars. For horizontal navigation bars, the order of the links need to be reversed. First link, which appears on the left for left-to-right languages / cultures, would need to appear on the right.
Another example is vertical navigation bars. Right-to-left cultures actually expect vertical navigations bars to be on the right of the page, not on the left.
I’ve seen this as left / right versus reading-order / anti-reading-order.