The release happened as a result of a decree of Open Government from 30 October 2019 after the French government joined the Open Government Partnership in April 2014. After two years of work, the site hit version 1.0 on Wednesday.
This really allows further re-use of publicly funded code, and also serves as a boost for their own small businesses who want to make use of it for themselves or to serve their customers.
See https://www.theregister.com/2021/11/11/french_government_foss/