The real reason as to why aliens won't come down and finally make themselves known... Humanity. Humanity has gone off the rails with our species being too busy trying to figure out how many genders there are. Aliens wouldn't bother dealing with us. To them, humanity is nothing more than a colony of insects with barely any intelligence. Humans are the lizards that play chicken when a human rides a bike through a side walk, or a mosquito larvae trapped in a pool full of guppies. They have nothing to prove to us, but we may be a nice little pet. A gift for an alien lover.
We're a species that loves to war with each other and pretend we don't but then help support the wars either way through nepotism, lack of competent people, supporting of wars through proxy like taxations and good people making bad investments in the hands of evil men in power, because of blind obedience, etc. The list goes on and on.
Best to just visit them instead through astral travels.
We are the crazies of the Galaxy. Our planet might even be under quarantine for all we know. We do have an abundance of bacteria, viruses, etc that anyone off- worlder would be harmed by. Beautiful planet but filled with danger for them.