waauw wrote: I wonder about the reliability of this Pew Research, especially since religious surveys are illegal in France.
Wikipedia:The Pew Research Center is a nonpartisan American think tank (referring to itself as a "fact tank") based in Washington, D.C. It provides information on social issues, public opinion, and demographic trends shaping the United States and the world.[3] It also conducts public opinion polling, demographic research, media content analysis, and other empirical social science research. The Pew Research Center does not take policy positions, and is a subsidiary of The Pew Charitable Trusts.
Media Bias Fact Check: Overall, we rate Pew Research Least Biased and Very High for factual reporting due to excellent sourcing.
In review, Pew Research primarily is a polling and survey outlet that utilizes and publishes their methodology.
A factual search reveals that Pew Research has never failed a fact check. In fact, Pew information is used by fact checkers to verify data.