I think that a lot of the post WW2 panic over nuclear weapons has pervaded the UFO argument. There was at that time a lot of guff on how we would alter the balance of the solar system/galaxy/universe etc. which was worrying the ETs.
Even if we let off all the nukes we’re unlikely to do anymore than wipe out ourselves and a lot of other species, we may mange to wipe out all life on Earth but even that is unlikely.
Any attempts by whatever the UFO occupants are to stop our path to self destruction can only be because: they are from the future and the past is alterable ; because of concern for us or some other species, or concern for a biosphere that they have a use for – with or without us.
The best evidence is contactees or witnesses claiming a spiritual experience following contact. But this would be better applied to politicians than Mrs Ethel Scraggs of Birmingham.
Otherwise, what are they up to?
“Hey Zxxork, how do we stop the bald monkeys from destroying themselves?”
“Lets, play tag with their jets, kill a few cows and probe their bums.”
“What is it with you and probing bums?”
“Well we don’t have them and I find them fascinating.”
IMHO I think that if they have made contact in any way we can understand it is to try and raise consciousness via creating religious leaders and that has mostly gone very wrong because of organised religion (Life of Brian) Perhaps they are having a re think.
As an aside the FT article on finding random numbers was interesting – we always look for patterns for communication perhaps they are transmitting true random signals as proof that they have created them? I think Sagan once said something similar.
The real problem is that we have no way of knowing the motivations of a truly alien species. Indifference is one we may find hardest to take.
Apologies for the rambling.