If the point of education is to enable you to get more education at a nicer class of school, humanity is doomed. I have been to one of these international kindergartens and I found it a depressing experience. Learning letters and numbers and parroting sentences and coloring in pre drawn pictures with a colour scheme set by the 'teacher'.
I feel lucky my children went to a place where learning was through self-directed free play, and there wasn't a desk or a letter formation sheet in the place. And yet three of them were reading and writing before primary school, and the eldest now is now a research scientist. Early experiences are so important, the opportunity for learning should never be lost through formal teaching of under fives.