I am unsure OP, what premise you are working on. Are you saying there is no alien life in the entire universe? If you believe that, you could have
struck out 90% of your post, as it only stands to reason that if there is no alien life anywhere, then obviously, it follows they can't be visiting
us. Perhaps all your effort can instead be put into that theory, instead of trying to follow up with "there is no alien life.. AND those non-aliens
are not visiting us" angle.
Of course, I would hope you wouldn't be so arrogant as to assume you know all about life in the universe as a whole. How could you know? You
can't. It's impossible for you to know. A theory isn't proof, you know.
As far as visitation on our planet, there is plenty of evidence that isn't dots of light in the sky, and eyewitnesses that are not kooks wearing UFO
hats on their head at conventions. Making a comment that 99-100% of sightings are explainable is also a laugh, as 100% of sightings have not been
explained away with any sort of proof. If you have in secret, done extensive research on all the many solid cases, and have discovered the answers,
I'm certain we'd all be delighted to hear the results! We've been banging our heads against some of the thornier cases in some cases, for decades,
so it's a relief to know you may have all the answers.
You may not realize it, but many UFO believers do not believe every blip in the sky is an alien craft, nor every crop circle is a mysterious message
to our species. You paint with a very broad brush. Also, you have the habit of doing what many here do... they debunk the ridiculous, while
completely ignoring cases with merit. When in doubt.. pretend that sighting doesn't exist.