Why Aliens never came to us?

With all sorts of documentaries and viral videos which surface every now and then on the internet which some how relate to either we being looked upon by them and how our ancestors mistook Aliens as Gods about thousands of years ago and few videos claiming that we have found them but as an neutral spectator i can tell with utmost confidence that t
hey are not going to come.
Because of a simple reason called logic.

Their are so many instances when people have been claimed to have been abducted for scientific experiments to alien space ships and some claim about spotting a crash landing or merely a bright light in the sky which moved from here and there.

People will agree with me that aliens spotted by them in our atmosphere where at-least as intelligent and technologically advanced as us if not more
Then how is it remotely possible that a species which is millenniums ahead in technology who have the ability to travel vast stretches into outer space will need to abduct a person to experiment, they can simply send a nanobot resembling a mosquito and get the subject's blood sample with which they can get all the biological data required and the know-how in the internet to experiment or even reproduce a clone if need arises.

Moreover people have spotted crash landings of space ships which have traveled light years without a scratch meanwhile even with today's technology crashes are uncommon given the no. of flights which take off every minute to our skies
.
Now lets deal with bright flashes of light in the sky which have caught our attention quite well thanks to mobile cameras but do these people ever thought how bad people who have been working on stealth technologies  feel when people talk about these sightings then imagine how traumatized the space ship designers of these Aliens would be after hearing the claims of us sighting theirs.

"A species which has the capability to go interstellar but doesn't have a stealth capability" perhaps they should sign a MOU with us for technology transfer and then we have the ancient alien enthusiasts who when spot an ancient structure which seems advanced and deserves credit believe in labeling it as a work of Alien civilization because we think how can a civilization so old can create these structures without today's technology when we are struggling to fix our highways.

Their can be many claims and counter claims but we need to ask ourselves that would we be behaving in the same way when we step into their shoes after some thousand years and will be looking forward to visit a planet like ours?