My problem is thst you are assuming that all these obstacles would favor complex life over simple life. (i dont grant this assumption and you haven't support it)
That's not what I'm saying.
What I am saying, is that life would have required a minimum of biological machinery to deal with these issues. A minimum that necessarily would have to be more complex then life forms that do not have such machinery, like first life.
I'm not even claiming that the mechanism to defend against oxygen must be "complex" or whatever.
But it is pretty obvious that a simple lifeform WITH the biological machinery that defends against that (however complex or not it might be), will be a more complex organism then one that does NOT have such biological machinery.
First life would not have had such machinery.
It's not rocket science.
Life that has defenses, however simple they might be, is going to be more complex then life that has no defenses..............
When the fact is that often the best way to deal with obstacles is by becoming simpler
First of all, it's not necessarily "often".
Secondly, this is true for organisms that are
already complex.
The simpler the organism, the less likely it is going to succesfully mount a defense against a new threat by becoming even more simple.
And if you are that simple that you simple don't have the required biological machinery to set up a defense against anything, then you necessarily aren't going to set up a defense unless you acquire such machinery which allows you to do so.
Why? Why is it unreasonable?
I've been trying to explain it to you for several posts now, but it seems it's the same story as usual. In one ear and out the other, followed by a repeat of the question which was just answered and dismissed with but a handwave or just plain ignored.
Can you quote a single scientist who claims thatvthe idea that simple life survived for 4B years is ridiculous?
No. I also can't quote a single physicist who found it necessary to write in a report that the idea that hammers will shoot into space when you drop them on earth is ridiculous.
Honestly if we ever find life in other planets, would you say that it would be unlikely that life would be simple in that planet ? (assuming life is 4B years old)
Compared to what? See, "simple" and "complex" are rather relative terms. I'm not aware of any "unit" or "standard" to compare it to to give the terms meaning beyond subjective opinion.
So, I will answer this question from the various angles that I think are relevant.
From the perspective a complex multi-cellular eukaryote with the evolved cognitive ability that allows for pondering this question, I'ld say that I think it is quite likely that if we encounter life on another planet, that that life would be simple. Simple in the sense of that it seems likely that that life wouldn't be multi-cellular (using earth as a reference - most life on this planet isn't multi-cellular and for most of earth's history, multi-cellular life didn't exist).
From the perspective of the simplest of "organisms" that one would expect "first life" to look like, I'ld say that life on another planet would almost certainly be complex. If it weren't, I would expect that said life on that other planet was very young and we happened to stumble across right at the moment (*geological time*-moment) that abiogenesis just occurred, give or take a few hundred thousand years.
Would you say that it would be very unlikely to find something much simpler than a nodern microbe?
No in terms of complexity, I'ld expect it to be rather comparable to the range of complexity we currently find on this planet in unicellular organisms.