Desperate for more publicity because he stamps his foot but never gets enough, he has now made the most ridiculous and unscientific statement I've heard -particularly from him.
We are finding that water as well as other things life requires to exist are NOT as rare as we thought. The number of habitable zone planets detected has increased fantastically.
But, oh no, Cox KNOWS far more than scientists and astronomers who have spent decades longer than he (and he is NOT involved in SETI or CETI but a Physicist which mainly involves theorizing on what others have done) -in some cases 5 or 6 decades.
He is a stroppy, not very likable personality who spends more time making TV and radio programmes and promoting self than actually rolling up his sleeves and doing real work.
I once thought he had promise but...we all make mistakes.
Why are we not getting to contact "lots" of alien civilizations? Deep breath.
There has never, since Humankind evolved, been a period during which there was no war. Up to this point in time Humankind has killed BILLIONS of its own race because of greed, religion or because "it was fun". Add to that the countless billions of other forms of life -animal and plant, the way the Earth has been poisoned and ripped up -again for profit and greed. It has never stopped. It never will because after many millenia...it's on a roll. Humanity brings species it has been killing for no reason back from the edge of extinction just to hunt and kill again.
Watching and listening to our broadcasts, communications and even distant monitoring, any alien civilization would, at best, Quarantine Earth. You do not want Humanity spreading out further than this solar system.
For a script I once had to do one of those Star Trek "Humanity has so much promise and good" type speeches. In the Star Trek universe humanity is still fighting. Pointless speech. The one I wrote was: "Earth is a lovely planet. Exterminate Humanity but leave everything else."
This is why I keep stating that we need to look at every alleged UFO landing because somewhere (away from all the "Greys" fantasy) there may be one or two genuine accounts and that is hands-on Search for Extra Terrestrial life.
One day, a newspaper headline will read: "Mr Brian Cox Farts". It'll be far more honest.