What's really remarkable is that Hawking is the longest-surviving sufferer of ALS ever-- he was diagnosed at 21, so he's been living with the disease for 47 years.
People typically only survive the disease for about ten years; prior to Hawking, the longest documented cases were 32 and 39 years
On topic: the human desire to conquer and destroy everything isn't the only reason native americans suffered after Europeans colonized the Americas. Sure, there was a lot of that sort of thing, but Native Americans also died for reasons the Europeans couldn't
control: the Europeans brought over diseases which didn't exist (or existed in different forms) in the Americas and the natives had no natural immunity. So, even where there was peaceful collaboration, the Europeans were still responsible for death and illness
that they didn't even know they could have caused.
I could imagine something similar happening with extraterrestrial contact: we make peaceful contact with an alien civilization, but they bring along microbes that our unadapted immune systems aren't prepared to handle. Or they don't realize that their
hydrochloric acid-containing sweat is harmful to human life, or any number of things that you wouldn't be prepared for if you've never met an extraterrestrial civilization before.
There is absolutely no reason to believe that 'higher intelligence' (conciousness) is the inevitable outcome of evolution. The most successful and longest existing groups on this planet are not intelligent.
We tend to assume that intelligence is the height of evolution because we still see ourselves as the pinnacle of evolution, instead of just another phase in it's long history.
I believe that the rise of higher intelligence on this planet is a fluke; if we ever find any extraterrestrial life it will not be intelligent.