Modern examples of gullibility as evidence against Christian claims

[Oldandeasilyconfused]

Christianity has stood the test of time,

You seem to imply age bestows validity;it doesn't.

Many religions have come and gone

Indeed, but Hinduisms and Buddhism are both older than Christianity and the ancient Egyptian religion lasted for over three thousand years. Its moral code has much in common with Christianity.Be happy to provide some concrete examples if you like.

but Christianity is still here and doing rather well

Still here,yes,but how well Christianity is doing is a matter of opinion. EG in my lifetime, Australia has gone from an openly 'Christian' country to a secular one, as have most northern and central European countries.

Generally speaking,religion declines with affluence and education,and thrives in poverty and ignorance.