It seems to me that the biblical flood event fits current population statistics far better than a non-flood history
Of course, that's already what you want to believe. Confirmation bias.
That is, let’s assume it takes 150 years for the population to double on average. This corresponds to an average annual percentage growth rate of 0.463% (for every 100,000 people, a net of 463 are added yearly).
Why would he make that assumption? Did he normalize the data? Does he know what that means and why he should do it? Why doesn't he start with the biblical numbers?
In 4,500 years there would be 30 doublings (4500/150 = 30), so those six people would grow to 6.4 billion. This is close to today’s world population of 7.1 billion.
Ah, we see he makes that "assumption", which isn't an assumption at all, because it's the growth rate that fits the story he wants you to believe. He didn't follow the evidence or do any research, he simply did really really bad math to arrive at a pre-determined conclusion.
Did he calculate in the Black Death? Crusades? Genetic diversity? Incest? Anything else?
Thus the known facts of population growth fit the Biblical chronology very well.
No, no they don't. His assumptions and and contortions have been jammed sideways into the spaces between the known facts.