For You Were (Not) Slaves in Egypt?

My students are often very surprised that many Jewish people deny that that the Exodus every happened. But as this Haaretz story unfortunately hidden behind a paywall states quite explictly, 

"The Passover narrative is one of the greatest stories ever told. More than any other biblical account, the escape of the enslaved Hebrews from Egypt is the foundational story of the Jewish faith and identity, one that all Jews are commanded to pass on from generation to generation.
 
"Also, it never happened."

This is akin to Christians denying Jesus' resurrection which unfortunately some do. Sad all the way around.