Comment by derbOac

One thing to keep in mind is that some teas (as in made from Camellia Sinensis leaves) are processed using a pan/ceramic firing or steaming step to stop the leaves from oxidizing. I'm not sure how hot it gets but there is a heating step that might affect the viability of some pathogens.

It makes sense that herbal teas might be more susceptible to pathogen contamination if they don't go through that.

Of course there's plenty of steps along the way to contaminate tea, and chemical contaminants are different. But boiling water isn't the only heating step for some teas.

Having said that, I generally just use boiling or near boiling water for all my tea. I've tried all sorts of combinations of temps with many many different varieties of tea and have decided that the tea variety, amount used per serving, and length of steeping make much more of a difference than the temperature. I also think I just like bold-flavored tea (I do like bitter flavors quite a bit, and have been known to seek them out even when I was too young to really be aware of a pattern with it).