Why Kangaroos have short arms and long legs

I just read an article about why kangaroos have short arms and long legs. In summary it’s because that suits them best for what they do i.e. crawl in a pouch or hop around…
Why does this go down as an historic discovery? Well, maybe not historic, but at least noteworthy. Because someone just discovered another reason why evolution is so awesome. Really?
It’s like saying, “I just discovered why televisions have remote controls! They evolved that way because having a remote control makes it easier to change channels. Isn’t evolution great!?!” Really?
In an age of scientific progress, tautologies have become noteworthy discoveries.