The Jewish holiday of Passover and The Christian holiday of Easter usually happen around the same time each year, as is the case this year.
Jews are not suppose to eat bread for eight days, just matzos, (unleavened bread,) like a cracker since the Jew's when on their exodus from 400 years of Egyptian bondage and slavery were set free, and when on the move, bread did not have time to rise. However for the seder we have the time to make Matzo ball soup, Jewish fish balls called gelfilte fish, Brisket, salmon and delicious salads.
My guess is that the Jews did not have time to cook that elaborate if they did not have time to bake bread?
Breads another story, since flour and water in heat will eventually sour and make it's own leaven (yeast) therefore I actually believe the Jews ate some leaven , just because it is a natural process and it is hot in the dessert, in fact flour and water is how to make true sourdough starter.
The Lord on Judgment day is not going to say, you were bad because you ate bread at Passover, he may say you were bad for not obeying the ten commandments.
It's amazing how man can interpret history and especially the bible to satisfy one's ego.
The Easter bunny, that's another story....