There was a time, before science discovered more about our solar system, when non creationists, basically were sure, that the close universe would be teeming with life.
What they found, were a bunch of inhospitable planets.
Life from elsewhere, theory, the best at the time, took a big hit.
OK. This could be an interesting thread, but first, let's clarify our terms, or we'll end up talking past each other.
When you say "non creationists," are you talking about scientists who don't believe in creationism, the average Joe with neither knowledge not interest in the subject, or something else? By "creationism," I'm assuming you're referring to The Christian doctrine that a God poofed the universe into being by magic?
l don't think there was a time when non creationists were sure the solar system teemed with life. Yes, there was speculation -- canals on Mars, people on the moon seen through early telescopes -- but this was just speculation, by people who really knew nothing about the bodies in question, or even about basic biology.
Nobody was "sure" of anything. A few speculated, that's all. That ended when the unfounded speculation did; when scientists learned something about the planets and found conditions there were inhospitable,
"Life from elsewhere theory:" Now this is a whole different premise from your first: that life
existed elsewhere in the solar system. You've introduced a new, unrelated concept, and one that has not taken any 'big hit'.
You call it a 'theory'. How are you defining "theory?" In science, theory is not speculation.
The further away the proposed, "source", for the plants etc, on earth, the more unlikely
Not sure I'm following here. Are you talking about panspermia, abiogenesis, or something else? What are you saying is unlikely?
The proposed earth timeline, even taken to extremes, is problematic for the fabled "primordial swamp", and now the distance for interplanetary probability is surpassing sci-fi believability.
Again, I'm not following. The proposed 'earth timeline'? timeline for
what? and what is this primordial swamp?
If this is a current theory in biology, what does it propose, what evidence does it present, and why is it 'problematic'?
Where is the evidence for anything besides creationism?
Where is the "evidence" for creationism? Creationism is a proposal of magic. There is no 'evidence' supporting it.
I think you're proposing a false dichotomy; that if a natural origin of life is discredited it constitutes evidence for your supernatural proposition. This is illogical.
There is overwhelming evidence for a natural origin and development of life. If you have any evidence of a magical origin please present it.