I'm probably in the minority around here if I state I'm sorta fine with a whole lot of languages being lost to time.
Are there things we could have learned from them that are lost to time? Well, yeah, and that itself is bad, but preservation is simply not feasible, same as we don't store every single piece of information nowadays, we can't store all of language for the same reason it's interesting in the first place: It's alive.
It's also worth noting, there's a whole, whole lot that is bound to be uninteresting beyond historical knowledge and that deserves no more respect than, say, food.
Are there things we could have learned from them that are lost to time? Well, yeah, and that itself is bad, but preservation is simply not feasible, same as we don't store every single piece of information nowadays, we can't store all of language for the same reason it's interesting in the first place: It's alive.
It's also worth noting, there's a whole, whole lot that is bound to be uninteresting beyond historical knowledge and that deserves no more respect than, say, food.