Learning multiple languages has been shown to provide many benefits to a child's wellbeing, though I don't see anyone forcing anybody to learn or use the language.
>If young Ojibwe people are choosing not to use it, then maybe it's because they don't want or need it.
Kids stopped using it because they are shipped to residential schools that used to punished use of their nativity language. There was no "choice" offered.
That said, the preservation of endangered languages is definitely in of itself a valuable and noble pursuit of knowledge. It preserves our understanding of the past, at the very least. And for something more groundbreaking, there is the whole matter of the Pirahã:
That's a misunderstanding of Treuer's point. English is able to define English nations and express the English cultural perspective. He's not arguing that language, generally, is a tool for communication - he's saying that specific languages each yield their own specific identities.
To address the point more generally - languages do, for most speakers, have an influence on thought. People acknowledge that effect to varying degrees, from "you can't think what you can't express" to "language is intertwined with culture and culture differentiates thought" (i.e. not quite Sapir-Worf).
As an anecdotal argument - monolingual speakers often expect translation to be one-to-one, bar idioms. The fact is languages differ in nuance for different kinds of terms, to the point where a mapping might be one-to-many, many-to-one, or completely absent - and those nuances can and do reflect different cultural attitudes. For example, there is no English equivalent to wel[1], the Dutch word for reinforcing a positive sentiment.
Does it need to? If a language interest a community, then it's reason enough to learn it.
Anyway, if you're a deaf person, a sign language is going to be a hell lot more useful than a spoken language, since the deaf can effectively communicate in say...ASL, as opposed to spoken English. They do still need to learn English, if only to interact with the larger community.
And ASL is interesting because you can some ideas communicate ideas more effectively than you could do through spoken words. ASL has a lot of opportunity for iconicity.
I learned it because I am curious about the language with no practical application in mind, but hopefully one day in the future, I will use it to communicate with the deaf and that will be one of the coolest way I will ever help a person.
I've nothing against people voluntarily choosing to learn a language. But most language learning is done by children who are heavily pressured if not outright forced into it by their parents (who usually, hypocritically, do not put the same time into language learning themselves). That's cruel in my book.
They have a much greater chance of contributing to humanity if they have access to all that a common language provides.
So what that a monkey is a "lice hunter"? In English, an anteater is an anteater and a wood splitter is a wood splitter. It's not a very special way of naming things. Maybe this language has no value to anyone except its own users, but they already speak it, so no effort is needed.
These activists always have a dark intention in their ideas that they want some poor indigenous people to be burdened with the work of learning and using a dying language. If young Ojibwe people are choosing not to use it, then maybe it's because they don't want or need it. I also didn't learn much Morse code as a kid despite older people wanting me to. Turns out it's no longer as useful as it was back in their day.
"Language, Treuer says, defines nations, connects generations and allows a culture to express its perspective on the world." Yes, and English does that job much better because you can actually communicate with the world and multiple generations. Different cultures do alter it with local slang or styles of speech and it's still intelligible while also defining their identity.