>>20833072it depends on where you are. a lot of our water infrastructure is lead, which, counterintuitively, is actually fairly safe if well maintained as lead forms a very consistent non-reactive oxide layer when exposed to water but the lead piping in america is very old so it has fallen into some degree of disrepair and can contaminate water. in addition, not everywhere has the same quality of fresh water sources or water treatment systems. the reality is that in most of the country the tap water is fine it might just taste kinda shitty.
having said that ive drank tap water my whole life to no discernible ill effect because where i live its perfectly safe and tastes fine.