With the size of space and the number of stars and galaxies in it, it’s hard to imagine that we are alone. There are at least an estimated 100 billion stars in our galaxy, and 2 trillion galaxies in our universe (NASA.gov). For there to be no other form of life seems astronomically insane. Humans have used signals to call out to other worlds, but we have gotten no reply. If there is life out there and it is as intelligent as we are, why have they not replied? One reason may be that we are not ready to be contacted.
It takes a long time for light to travel to other stars. The nearest star is a little over 4 lightyears away. If there was intelligent life on a planet orbiting that star it would take almost 9 years to get a response from them. This also assumes that they have technology that can not only receive and process our signals, but send signals to other planets as well. It took life on Earth about 3.8 billion years to make technology that could potentially send signals to other planets. The odds that another planet has that same capability at the same time we do and is in a close enough proximity to Earth to get a response anytime soon is not very likely.
We may be considered too primitive to interact with. In the North Sentinel Island in the Andaman Islands of India there is a tribe of people that refuse contact with other humans. They are still in the hunter gatherer phase of technology. We have not refused communication with extra-terrestrial beings, but we could have previously tried to have been contacted but didn’t know it; like if you were to use a ham radio to send a signal to the North Sentinel Island, those people would not be able to respond to you. E.T.s may also see our technology and minds as too primitive to communicate with.
Another reason for not being contacted by E.T.s is that we may be too violent for any of them to want to contact us. Humans have the potential to wipe them selves out with the power of the atom bomb, and have come close to all out nuclear war in the 60’s. We have had consistent wars between each other since always. We are also seemingly obsessed with finding better ways to kill each other; like discovering the awesome power of the atom, and turning into a bomb, or inventing a way to share information through connecting every computer, and using it to spy on an entire nation. If there is a species capable of contacting us or travelling to Earth the chances are that they are far more advanced than we are. If we were to get a hold of their technology what would we do with it? History shows we would find a way to hurt others with it.
Humans are at a very sensitive time in our evolution. We are at the earliest stage of becoming a multi-planet species. The advent of artificial sentience is more of a “when” than an “if”. Advances in medical and Nano-technology could allow us to live well beyond our life expectancy. But with very step forward we could be getting closer to a cliff. That cliff could be the fall of human civilization, a war that utilizes our most advanced technologies to kill more efficiently than we have ever seen, so efficient that we eradicate most life on Earth. That cliff could also be a launching point where we break away from our tradition of war. We use technology to end war and global suffering, and become a space faring species. This may be what other more advanced species are waiting for us to do before contacting us. This could be our trial period, the time that maybe all species go through, a time that they either advanced so far that they were able to bring about a mass extinction, or the time that they advanced so far that they prevented any more.
You bring up an interesting idea of intelligent life existing but not interacting with us because we are too primitive from them. A lot of science fiction use this a basis for their plots and is a perfectly plausible reason why we have not been contacted yet.
However, I would have like to see an alternative ,perhaps a small paragraph, to why we have not been contacted yet. Other than that aliens are vastly superior they are too primitive to understand/contact us. You mention the tribe in India that would not be able to contact us in return since they still have the hunter-gatherer technology still.So why not make it that the life on other planets cannot return a signal because they are too primitive.