Extra terrestrial why not ??
I find it impossible to believe that Earth is the only planet in the entire universe where the conditions allowed intelligent life to exist.
If you believe science at all, they tell us they’re billions and billions of galaxies in the universe, within each galaxy, billions and billions of stars exist, somewhere in that exist planets that have some form of intelligent life.
Some of the life might be hundreds of thousands of years ahead of our technology, some are hundred of thousands of years behind our technology...
If some life form has developed a way to get here, they are using technology that no one on this planet has even dreamed of, which means they could come here and not be detected.
The idea that we now can possibly detect UFOs means they want to be detected.
I have no problem believing that such “conditions” have never existed on other planets, nor on Earth itself, if what you are implying is spontaneous generation of life from non-life, without intelligent action.
Your premise works only if there is indeed billions and trillions of years(equivalent) of time. Reduce that variable to say, 100k, and your logical argument falls to pieces. Just saying, like evolution on Earth, all this ET life out there stuff hinges on an assumption based only on one virue, the “God” of time.
Or they might be a little sloppy. What was the movie where we are transported into the future and humanity has become so lazy and low IQ that the common man of today appears to be a genius in the future high tech society?
My personal opinion is that once a civilization develops space habitat technology, they cease to be planet dwellers, mining the Oort clouds of stars as they diffuse across the galaxy.
Why bother with planets??