This is indeed very depressing. A very excellent book about the scope of this problem is "The Sixth Extinction" [1]. One crazy anecdote from the book: the author explains how rare it should be to witness any extinction of a species within one's lifetime. The average "background" rate of extinction is something like one per one thousand years. During the course of writing the book, the author personally witnessed something like five species go extinct. It some ways this is an incredible time to be alive, but in many it's the most depressing time one could imagine... ever?
[1] https://en.wikipedia.org/wiki/The_Sixth_Extinction:_An_Unnat...