TL;DR: it's more complicated than I thought. First, the law was introduced in 2006, so before it, circumventing DRM and publishing how to do it was not a crime. (Of course, publishing copyrighted works with no proper authorisation was already a crime, regardless of DRM.)
Then for a brief time, circumventing DRM was outlawed. But fear of foreign monopolies (most notably Microsoft) and free software lobbying eventually had those articles amended, effectively exempting research and free software from any sanction. The exact limits of the current law are still fuzzy, but it seems pretty clear that using VLC to make copy of a DVD I own is 100% legal in France.
Only if it doesn't have the CSS thing, which most commercial ones have.
Even though it's a silly protection, it still counts as a "protection" legally.
It's like that in Italy so I suppose it's the same in france https://www.gianluigibonanomi.com/diritto-copiare/