Please explain this clear Bible error.

what impact does this mistake, if it actually is one, have on the plan of salvation? How many errors are there in dates denoting human history accounts? History, being a set of lies everyone agrees upon, according to Napoleon.
Rather than concentrate on the beauty of Christ, we frazzle over meaningless details.

There are so many variables applying to existence, to look down one's nose at those that do not please us, is arrogant for sure. Infallible is one of those words we should not even use, since it implies perfection and their isn't any to be found. The Bible also gives an account of peoples living a long time ago. Gee, haven't lifestyles changed since then, eh? Look around you on this planet these days and you will still find 'styles' so totally opposed from ours in this country, for instance, it's amazing 'these' people live in the same century we do. Not forgetting that 'odd' is extant here as well.
But the unbeliever sees what he wants and uses what he wants to ridicule as you say, and it is a power issue, he has the power to do so. It is an immature expression of an infantile personality that cannot allow others to prosper according to the choices they have made. Like schoolyard bullies. In this I include Christians - many of which look down their nose at what they find disagreeable - forgetting that Christ said, "sheep have I that are not of this flock." "Many are called, few are chosen", and those not chosen are the judgmental, unkind, unforgiving.....etc.