>>64862247tea has to be dried and preserved, every element of the technique results in a different flavor and quality and that's not even mentioning the growing conditions and age when picked. different size/quality also changes the proportions of the flavors extracted, carefully rolled leaves vs broken up shit in teabags (and water temperature, don't overheat green tea). there are a lot of different tea preparations in asia, but the more important thing in the west is added ingredients like flowers, herbs, roots, fruit peels, spices, oils, etc. to give different fragrances.
europeans traditionally drank fruit and flower tisanes before tea or coffee were introduced, and that's not even mentioning preserved syrups. some stuff like rooibos and hibiscus aren't even tea at all and are local alternatives from around the world.