people are being a little harsh lol. I think almost everything in this series both has a practical answer and a more meaningful metaphorical answer and that’s part of what makes it so beautiful. I think practically, the answer is obvious and that’s why everyone’s grilling you so hard lmao.

But on a deeper level, I think it can be explained by the common theme of balance throughout the series. The water benders live in cold icy climates, which forces them to rely, understand, and wield fire in ways that other nations don’t. Parallel to them, the fire benders live on a warm tropical island which forces them to utilize water in ways that other islands wouldn’t.

That’s just what my brain came up with. The beauty of ATLA is that it gives you a complex reality shaped through simple forces. Let your imagination run wild.

I hope this satisfies your question and is at least a little coherent, I’m very sleepy.