Well there are more than 1000 different teas, and not every tea has the same ingredients nor the same quality.
In China for instance they say that the first cup is always for the enemy. This is why they throw away the first pot of tea to wash of all the pesticides, instead they use the tea then again for the second pot and then drink it.
People in China drink plenty tea, but not only. If they drink 2 litres tea per day then they usually also drink extra 1 litre of water.
Nevertheless the consequences of heavy tea consumption can damage your gut.
So better is also to drink sometimes water like the Chinese do.
And I can personally only give the advise to compare tea and tea prices. Sure there are those that cost only 1-2 $ for one package, but ask yourself why there are others that cost per gramm more than Gold?
Obviously there are huge quality differences. I prefer dragon balls, handrolled premium green tea, 100 gramm cost about 20 $. Tastes totally different than normal teas.