You missed one major motivator that can cause egregious cognitive dissonance: Tribal Belonging. Ask any person who leaves veganism for health reasons what happens to them socially if they confess to eating even an egg.

The vegans, flat earthers, Trumpers, Q-anon, religious zealots, and certain radical left social justice movements (for a few examples) all have one thing in common: an unerring belief in their group’s dogma, and total ostracism and even harassment for dissent or failure to conform.