My own theory is: ...until Mam is capable enough to have cosmic awareness (along with our technology) aliens will still be unreachable. When we begin to realize that we are not just a citizen of this planet, but part of the vastness of lifeforms and materials in the universe and immediate dimensions, that will be the time that we could say hello to them.
An ant living in a rainforest doesnt dream of giants humans living in New York City since they are not ready to comprehend it.
RE: We are not alone. The Universe is teeming with life, much of it far more intelligent and advanced than mankind