I have never understood how people can, even for a moment, take the anti-evolutionary argument from improbability seriously.
The probability of an event gives you no right whatsoever to draw conclusions about the truth of its occurrence.
Probabilistic calculations may be done and seemingly incriminating numbers and estimates may be presented, but the only valuable information to be gleaned from the results is how often something is likely to occur.
Yes, the approximated likelihood of life as complex as human kind originating through naturalistic means is very small.
It is a staggeringly small number.
We all agree on that.
But that does not mean that it did not happen.
In fact, it literally can not mean that it did not happen.
Because it did happen.
It happened right here on Earth.
It's not "just a theory."
The evidence is overwhelming.
End of story.
To base one's beliefs solely on the mathematical probabilities of events rather than on the evidence for or against them is foolishness of the worst sort.