The issue's quite complicated. Firstly, because languages die and this is a natural process. Migration, work, marriage. Lots of factors. Secondly, language death does not inevitably mean cultural death.
People constantly confuse language and culture and personal identity.
They're not all the same thing. The idea of preservation of languages and of the environment of languages is complex, contradictory, easily misunderstood but always important. Would this be something that would happen by nurtering a sense of the importance of these languages within the family home or would you try to change government policy. I think it's all of the those things. You have to come at the problem from all sides.