It is also happening in South-east Asia. However, eg. in Singapore, the people identified themselves less and less on their ethnic dialect group.
Most people here speak English and Mandarin, following China and Taiwan's footsteps.
I hope friends in the Hakka forum can help. The reason given for them being able to get on so well with each other is that both are Hakkas and use Hakka in their conversations. This event happened only a few years ago. When I can recall the names of these 2 persons, I will post it here.