I recently found this article in Evangelicals Now Magazine:
The Global Religion 2023 survey, conducted by market research service Ipsos, interviewed 19,000 people in 26 countries. It has revealed that ‘in countries where religious practice is high, older adults tend to engage in it more than the young, while in countries where religious practice is low, young people tend to have higher engagement.’...
Let me confess I missed this European survey 10 months ago. But it is better late than never.
The whole IPSOS findings can be read here (IPSOS, GLOBAL RELIGION 2023).
Among the data, 5% of non-catholic Christians in France, including Evangelicals