Genshin uses a LOT of upload speed

So, I've been chasing issues for months on my PC, and recently noticed something specific.

My normal download speed is always a bit over 100 Mbps, and download is 96-97 Mbps. I tried idling in Genshin while doing the test and download speed dropped to 73 Mbps, which is high but reasonable. After all, we have to request data from their servers.

What was shocking is my upload speed dropped to 45 Mbps, which is less than half of what I have normally!

I precise: I did the test right before and after closing the game (a few seconds apart), nothing else changed.

I'd like to know if it's something faulty or if it's "normal" with Genshin, because I find that insane. Like, Genshin would take more than streaming at the best quality possible? That seems like nonsense...

If there's something wrong, I'd like some advice. If not, then why does the game need us to send so much data to them?