Taiwanese Chinese are born of nationalism, Hong Kong (and Macao) Chinese are born of Capitalism and Mainland Chinese are born of communism.
It presents one with 3 completely and utterly different types of Chinese from a social nurturing standpoint. Yes, they seem like different peoples altogether, because they all came up in different socio-political and socio-economic siuations in a very broad sense.
Over the next 10 years or so, you'll see more balance between all chinese while westernized chinese will be nurtured by their new socio-political and socio-economic situations.