By abandoning Shabbat candles, Yom Kippur fasting, tallit and tefillin, shofar, Megillah, Menorah, sukkah, the Seder and so much else, they proudly announce how emancipated they are, and how they can now focus on the pure ideas and ethics of the Jewish tradition.
The thing they forgot was that human beings need symbols as well as theories. Freedom for example loses its meaning unless it is related to real people, situations and actions.
Holding a piece of matzah and saying, “This is the bread of affliction” is a powerful symbol which gives freedom a real meaning. Celebrating Israel’s emergence into freedom represents the Haggadah’s words, “In every generation a person must regard himself as if he personally went forth from Egypt”.
Rituals are like the buttons that keep a garment together. Without the buttons the garment slips away and vanishes.