WOW.
Snow is blowing so hard you can hardly see.
Now, about these lost languages ~ you can learn Ladino on the internet. You can also learn Mingo on the internet.
"So what" you might ask!
First, so you can understand what more than half of Jewish names mean, and Secondly, so you can understand Homer Simpson.
I don't speak Latin or Greek; however I can use a dictionary. If I need to learn what some names mean I can find a book written by a competent scientist which discusses that. If nobody bothered to write a book then I guess it's not that important.
Secondly, so you can understand Homer Simpson.
Now, what is the value in that? :-)
I think the value of each language is proportional to the total number of speakers of that language multiplied by the importance of written works in that language and divided by availability of good translations.
Some very old Chinese books were never translated, and they are insightful - so you need to learn Chinese. If you work for a Chinese company (in China) it probably is a good idea to pick up some Chinese.
However languages of small tribes often have no writing system, and there are no books written in them. Nobody is intentionally trying to kill those languages, they die all on their own, just because there is less interest in learning them, and few people to talk to in them. Or to put it differently: how much more valuable your message will be if you say it in Elbonian instead of French, for example? It is not a secret that some language sometimes offers a better word than some other, but is the society interested in a minute gain if it has to heavily pay for it in complexity?
It may be that in a few hundred years all languages on the planet will consolidate into one, just because it makes plenty of sense. Only die-hard scholars will want to read Leo Tolstoy's works in his native language; everyone else will gladly settle for a translation. In fact, that might be a good idea because it takes a long time to master a language, and your own interpretation of the text would be for many years poorer than a translation made by a professional.
If I were to guess, future chances of complex languages like Chinese, Japanese and Korean are quite limited. That's because it takes so long to learn the writing (and it requires an ability to recognize complex images.) Japan has Katakana, though; China has pinyin - but ultimately English is one of simplest languages on Earth, and at the same time most of scientific literature today is in English, and pretty much everything worth translating is translated into it... so eventually larger local languages will join the languages of tribes in disuse.