the Tea classified under 'hot drinks' refers to products of the camellia sinensis plant, such as green tea, black, tea, white tea, etc. Some concoction made of orange rind and lime leaves is only called tea because there isn't another word for it. The difference is camellia sinensis derivatives are not permitted by the WOW.
It is never explained what is in Tea that Heavenly Father finds offensive, although a lot of people assume it is caffeine, as that is a convenient justification to their friends. "oh sorry, it has caffeine in it'. That argument doesn't hold water, it's like saying pork was not allowed under the law of Moses because it had bacon in it.
Tea is not permitted because it is a commandment of our creator, nothing more, nothing less.
Personally, I would stay away from tea products that are consumed.