This isn't really about the noah story, it's about how feesible it is that the current human population we have now could have come from a small group pf people
Almost. A small group of (genetically) different people perhaps.
If you blindly apply arithmetics, yes a progression (or compound interest) can quickly add up to huge numbers.
But if you take genetics into account, the whole story becomes so overleveraged that is not even funny.
There is a reason why incest does not produce offspring and if it does it is severely compromized on many levels, as well as often unable to reproduce.
If I recall correctly, the absolute genetic bottleneck is 50 couples completely unrelated to each other in order to have any chance of survival.
If we are to accept genetics as they are (and benefit from the results of their research), let's not be intelectually dishonest and ignorant when it comes to the application of the same principals to our ancestors.