At any rate, I don't think anyone claims to offer a complete explanation for everything that exists.
The evangelical line is that the bible is both true and sufficient to understand all you need to know for salvation, not that it's sufficient to understand everything. All phenomena are not claimed to be explained or even described.
But that's really beside the point, the point is that, with our current level of scientific knowledge, believing in FTL aliens who are zipping around Earth and performing other stunts in violation of the known laws of physics is not different than believing in magic and demons. The only thing that's changed is your interpretive lens - one has a lot more cachet in a world where science fiction is more read than theology.
It's a apocalyptic stance that for some (certainly not all) creates a nasty dis-association with the here and now. After all if heaven/hell was always the only point, then this life is like a Las Vegas weekend. It's not our place, not our home and in 72hrs we're out anyway.
I wrote before evangelical theology is sufficiently ill-defined such that it can incorporate major changes in understanding which is a kind of consistency problem. Nobody with a dose of common sense about the prevailing attitudes in monotheistic religions would say detection of non-earth based life changes nothing. The old testament creation story is all earth centered, and all earth-man centered all the time.
You might enjoy Ken Wilbur's "Quantum Questions" in this context. He writes a mini biography on all the major 20th century scientists many of whom held a spiritual core although (as far as I can remember) not an American evangelical line. I think the book makes a good point. No scientist uses science as means to prove or disprove God/theology. And no scientists uses the Bible to disprove or prove rational facts about the world we live in. Either way it's a corruption of the other. Nonetheless the evangelical line and its literal take on the new Testament is what it is.
There is no God. We're not living in end-times. Satan doesn't exist. Final judgement isn't pending. Salvation is an unforced problem. And no proof of aliens or even bacterial life off-earth is demonstrated with rational evidence.
This brings us to a world more like Camus'. Existence is absurd. Meaning is living a full live despite the absurdness of it akin to Sisyphus pushing the rock up the hill to have to retrieve it when it rolls down and push it up again. Our job is to make something of that while we can.
I like Camus, and most would categorize my philosophical beliefs as some breed of Nietzschean, but I think it's very important to develop a deep an understanding of other attitudes as possible, and I don't think this is generally true. For example, CS Lewis is widely loved by evangelicals [1] and he literally wrote fiction laying out how he thought aliens would fit within that cosmology[2]. There is really nothing in particular that would change theologically. Of course it may change things culturally.
[1] https://www.huffpost.com/entry/one-man-thinking-cs-lewis_b_8...
[2] His space trilogy.
I'll try to come back in middle with a few things I also heartily respect:
- certain persons are able to wholly soak their life in Christianity and do right with it to the benefit of all. I think of my sister. I think of the Secretary of State from the mid-west (name and state forgotten by me) who was hit on to do illegal stuff around the USJan6 debacle. This guy calmly explained his position to the Jan6 commission centered in his belief and his duty to God with its moral underpinnings. And he did as an authentic individual. No stock phrases like "As a Christian man" thereby putting emphasis on identity or grandstanding. He earned my respect. He knew the right thing. He reasoned the right thing. Then he did the right thing. Gotta admire that.
- religion was our first kind of shared culture. It provides some guidance on moral and ethical behavior. My parents (really my mother) raised me broadly under this background and it did right by me. Duty, knowing and doing the right thing even if it's temporarily uncomfortable, and having humility are important. Now, I'm leaving out square light years of details and nuance in so saying, but I acknowledge a good thing is good.
On aliens: my goto hunch is sensor spoofing either by creating a signal that's sensed and misinterpreted as bonafide, or a hack in the sensor systems itself. Demons? ET? These are extra ordinary phenomena that are gonna need extra ordinary evidence.
In conclusion I'm heartened we both ended up with one foot in Camus. The French aren't half-bad at philosophy! Cheers.