Why have we not found any aliens?
This is the year 2017. We have electricity, computers, space ships, radio, TV, cell phones, internet, driverless cars, oh and so much more.
With lots of communication devices, why have we not been in touch with living beings from outer space?
Funny, I was thinking about that while weeding in the garden this afternoon, and I came up with a few reasons.
Probably number one on my list: Because there are no aliens. There is nobody out there, just us.
Another reason could be that we don't have the right technology to make contact with possible beings out there. Just 100 years ago, we have close to nothing to communicate with each other if we lived far away from one another. Have we really that far advanced in 100 years, or do we just think we've advanced and made progress? The means of communication we have today are probably nothing compared what our grandchildren will have.
And more... if there are living beings out there somewhere, they could be too far away. We all know how big the Milky Way is, but that is just a tiny spec in the universe as far as we know. If we have neighbours, they could be so far away that we'll never cross path or get in touch with them.
Probably what we need to do is go out and look for them instead of sitting at home and waiting for them to send us a signal that we can detect and interpret. You are right that their communications technology might be very different from ours. They may be telepaths and will have developed technology that enhances their telepathic communications, for instance, and that's something that we wouldn't pick up on because we would have no way of interpreting such a signal as anything other than a hallucination or delusion. There's also the fact that many planets will have life but not intelligent life with advanced industrial capacity yet. There are moons orbiting Jupiter and Saturn that have all, or at least most, of the "ingredients" required for carbon-based life, but none of them are emitting artificial radio signals, likely because none of the theoretical life-forms on these moons have the technology yet. But I consider it incredibly unlikely that there is no intelligent life elsewhere in the universe. Maybe we're just boring, so they have no interest in talking to us.