How much data does GW2 use up?
If you have the game already, open resource monitor, go to a world boss, and watch the amount of throughput the processes uses. World bosses are about as big as it gets (possibly surpassing WvW by a significant margin), and you can use this get your peak usage.
Check out the recent thread, which asked the same question:
https://forum-en.gw2archive.eu/forum/game/gw2/Data-consumption/5249867
There are some very useful responses.
John Smith: “you should kill monsters, because killing monsters is awesome.”