Of course you can't expect proper tea in a typical American restaurant. No one in the establishment ever drinks it. For those of us who do like to drink it occasionally, it is an acquired taste, to be indulged in the privacy of the home.
Americans find English habits just as peculiar. Personnel in many restaurants don't seem to understand that many North Americans like their coffee with a meal, not just after it. The restaurant tea is just as bad; much of it, like the American Red Rose, lacks any real taste.