This means something one finds pleasing though it’s more often heard in the negative – but that’s not everyone’s cup of tea.
Tea is, or most certainly was, the national beverage of Britain and it gave rise to lots of idiomatic phrases such as ‘storm in a teacup’ and ‘not for all the tea in China’.
Something described as one’s cup of tea was something held in high regard, just as the soothing brew was savoured.
Nancy Mitford wrote in her novel Christmas Pudding in 1932, “I’m not at all sure I wouldn’t rather marry Aunt Loudie. She’s even more my cup of tea in many ways.”
While tea remains popular in the UK the idiom has moved to the dark side. An example is this Guy Pearce quote explaining why he didn’t want to play a superhero, “Comic-strip stuff isn’t really my cup of tea; really.”