@kevinrns @Di4na @linuxiac Unfortunately that's not what the original source says (which they helpfully link to):
https://www.numerique.gouv.fr/sinformer/espace-presse/souverainete-numerique-reduction-dependances-extra-europeennes/

The move off Windows to Linux is specifically for the DINUM itself. The mandate for all ministries is much looser: a plan for "reduction of extra-European dependencies".

That can mean a lot of things. The DINUM Linux migration is one of three examples they give; the other two are about various SaaS services.