The ranks of dead languages are about to swell. The world is a much smaller place than it was even fifty years ago. Languages which I see sticking around or being necessary in any sense include:
- English and German: Learning any other Germanic language is a waste of time.
- French and Spanish: Learning any other Romance language is a waste of time.
- Russian and possibly Ukranian: Any other Slavic language...
- Japanese and Chinese.
- Hindi: Any other Indic language is a waste of time with the caveat that Sanskrit will still be studied by scholars.
- Hebrew and Arabic: Any other Semitic language is a waste of time.
Languages which the world no longer needs would certainly include Portuguese, Danish, Swedish, Norwegian, Italian, Korean, Dutch, all Indian state languages, all African languages, all Australian aboriginal languages, all Polynesian languages, and generally the bulk of the world's present languages. Making a child learn any of those languages is basically child abuse and could certainly in no wise be viewed as preparing him or her for life in the modern world.