The linguist John McWhorter wrote an NYT opinion piece entitled Why Save a Language? where he argues why we should care about saving dying languages, basically that language gives us a window into culture. As a computer scientist I appreciate the scientific value of studying languages but perhaps the question is not whether we should care but is it ethical to save languages?
Languages developed on geographical and geopolitical boundaries. Even as new methods of communication came along such as postal mail, the printing press, the telephone and television there never was a strong reason to learn multiple languages save for some small European nations and some professions such as academics and politics.
Then came the Internet and location mattered less but language barriers still persist. I've certainly noticed a marked increase in the number of young people around the world who know basic conversational English, much from the content they consume online. There's also a sizable amount of content in all the major languages.
But if you speak a small language where all the other native speakers are geographically very close to you, you lose this networked connection to the rest of humanity. Your only hope is to learn a second language and that second language might become a first language and so many of these small languages start to disappear.
I understand the desire of linguists and social scientists to want to keep these languages active, but to do so may make it harder for them to take advantage of our networked society. Linguists should study languages but they shouldn't interfere with the natural progression. Every time a language dies, the world gets more connected and that's not a bad thing.