The night sky is full of stars, and every one of them is a sun.
There are more that you can't see than there are that you can.
The day sky is similarly loaded with suns but you can't see them because of the light from our sun.
It is a pretty wild sort of a theory suggesting that none of them support planets with life, and an equally unlikely suggestion that none of that life is more intelligent and advanced than ours.
Typical human arrogance.
It hasn't even been proven to my satisfaction that we (humans) are the most intelligent creatures on this planet, let alone anywhere else.
Of course there are UFOs. They are smarter than us. They know better than to try to make contact.

John