French culture has some inconsistent, fascist, illiberalisms, especially in the differences of making fun of Christianity vs. making fun of Judaism, or similarly with Christianity vs. Islam. (govt demanding firing of Sine). Actual progressive liberalism should at least include listening to other viewpoints, being open to new ideas and generally being sensible and constructive. But narrow, identity-politics labels aren't all that useful in reality and end up inventing wedge-issues and false dichotomies. (There are some people looking for common ground while others are looking for Sayre's law fights.)
Sine was basically implying the religion was nothing but a tool of social climbing in that particular case. That's just an incredibly nasty, low and personal thing.
Je suis Charlie