We humans are on the brink of incredible technologies; let's face it, these "advanced technologies" scare us to death as we think of how they could be (and probably are being)-misused.
Nano technology: I do not pretend to be an expert on it, or even educated enough in that field to write in detail, but we have all read the theories of nanotechnology being seeded into humans, or replacing humans with nano-humans. There are lots of variations.
Cloning: There are endless nightmares here, from armies of super-soldiers who are the same guy, to Hitler and Stalin being cloned, to the super-rich cloning their loved ones over and over.
Ion power: NASA is using it for their deeper space probes. This form of propulsion is straight out of science fiction and of course could be (is?) used by power hungry leaders, for bad purposes.
The list is endless regarding new technology possibilities and the negative ways it could be used. Of course this includes super-computers and general computer advancement which is bewildering, to put it mildly.
Then, we tend to transfer the concept of "negative uses of technology almost advanced enough to be magic," to the aliens. They obviously have advanced propulsion methods and probably they have all our incredible technologies and more, and in our conspiracy-theory zeal, we tend to assume the aliens use all these advanced technologies to do bad things.
We assume the aliens are technologically super-advanced but morally/spiritually super-primitive.
Perhaps we humans project a bit, because the history of our race is to use new technology for aggressive purposes. I am sure that whoever discovered fire, soon had it stolen out of her hands (or her bonfire), taken by the ruling cave lord, to conquer the cave lord down the hill.
We keep advancing technologically, and as we do so, we always make the same mistake. We use the newly discovered technology for purposes of aggression and war.
In 1945, the United States dropped nuclear bombs on two Japanese cities. The consequences are unthinkable today, but they were the consequences: In Hiroshima alone, 80,000 men, women, and children were killed outright. 90,000 to 140,000 men, women, and children suffered horrific radiation burns and the suffering continued for years afterward. Urban Hiroshima was decimated - we all know the tragic truth.
Today, the specter of nuclear war, and of countries dropping nuclear bombs on other countries, has greatly diminished, at least from the larger "super-powers."
My point: Looking at all this in a positive light, we misuse new technology at first, but as time goes along, we realize that we cannot ethically and morally use it to conquer others. That is the pattern of human civilization.
Oh, but bad news: By the time we realize this, another new technology comes along and we have to learn the same hard, tragic lesson, all over again - this time with brand new technology.
However, it seems to me that our visiting aliens must have been through this similar cycle of "life form discovers new technology, life form misuses it, life form learns, life form becomes enlightened on the new technology, and then does not misuse it again."
The aliens must have been through this syndrome many times. After all, to arrive at the point in development where you can travel the vast distances of space, and/or the quantum puzzles of time/dimension, you have been through a lot in your previous history.
Then finally, you have devoted your race's resources to reaching the stars, and for traveling to other multiverses. Species' aggression is a deterrent to the progress of achieving astounding accomplishments like space and dimension travel.
That's why it seems illogical that obviously advanced life forms (the aliens), would arrive on Earth planning to eat us, or to clone us, or to use some mystical juice we have to rejuvenate their race. There are of course some cold scientists who have visited us, but there is not really evidence of them interfering in our human timeline significantly. And the majority of experiences and encounters with UFO beings, might be frightening to the humans involved, but it is hard to separate human fear and panic at the alien-ness of it all, from the equation. The large majority of the humans involved, seem to emerge from the experience intact.
Long story short, no one should arbitrarily decide to embrace negative UFO experiences as doctrine, and throw out positive UFO experiences because they are positive. The positive experience might possibly be because that human-experiencer was not as scared, not as panicked.
There is obviously more than one type of alien race in Earth skies. No one says they are all "love and light." However, I do see evidence that they have not used plasma technology to fry us all, they have not sent ion bombs which-do something unspeakable. They did not plant nanochips in their abductees which have caused these people to pick up an automatic weapon and kill as many humans as possible (humans do that, but they are not, to anyone's knowledge, the same humans who ran into a UFO).
I am hoping that in the same way the United States has moved away from dropping nuclear bombs on wartime adversaries like Japan (yes, I know the U.S. uses depleted uranium weapons but maybe one day soon, we will not), the UFO occupants have moved away from using their advanced technologies for bad purposes. Perhaps a few millennia ago, they had their last experience with aggression which used the technology they now have harnessed, to travel the stars.
Moral and spiritual advancement does move along with technological advancement, albeit, much more slowly. Massachusetts does not burn witches anymore, and the majority of American citizens would be morally repulsed if we dropped nuclear bombs on Japanese cities today - or even on North Korea. We do move ahead morally and spiritually, we do have the Magna Carta. We are more enlightened than the cave people were.
If the same or similar momentum applies to alien civilizations, then they too moved ahead morally and spiritually as their technology developed. Perhaps it was not at the same rate, it seems technology usually wins the race, but look at how advanced the alien technology must be! I feel it a good bet to think - or at least hope - that their spiritual and moral codes are advanced to a great degree, also.