Historians and many Bible Scholars inform us that the events of the Exodus are very largely embellished and legendary. Most likely the Hebrews do have a past in Egypt as servants, from which they somehow escaped. But the story we have, historians tell us, is largely legend and myth.
But the historical reality is not really what Passover is about. Passover is about liberation from bondage, both personally and politically.
Personally, we are all in bondage to various "Pharaohs": be it ignorance, personal failure, selfishness, anxiety, we are chained to personal captors. The message of Passover is that we can be liberated by centering in the Divine. Indeed at Passover the celebrants are called to recognize that no only their ancestors but they too were slaves in Egypt. Clearly this does not mean that they were literally enslaved in the ancient past, but that in their lives they have been in “bitter bondage.”
Politically, the story of Passover affirms with great clarity that God is not on the side of Pharaoh or any empire. God is not on the side of those with power, wealth, and privilege; Rather, God is on the side of the oppressed, the downtrodden, the exploited. Indeed it is this political aspect that is most crucial to this story. And especially at Passover all should ask themselves, are they with Pharaoh? Or with God? With power? Or with justice and liberation? Are they with with the God of the Exodus or of the Empire?