I drink tea for health benefits. I've done quite a bit of research, too, and my nutritionist encourages drinking it.
I think if the tea is steeped/infused in flouridated water it does make it dangerous plus remember that the tea leaves are natural sources of aluminum and flouride. There are other components found in tea, like caffeine, tannins, and such which can cause problems, too, but tea is like the ying and yang - there is the good and there is the bad. You can get skeletal or dental flourosis, but drinking tea also protects your body, too, as it is a strong antioxidant.
Considering that my Chinese ancestors (and the Japanese, too) have been drinking green tea for for over 5,000 years I will go by that.