They link to the document that shows the plagiarized sections side by side with their sources
https://v42.arretsurimages.net/fichiers/documents/2024-08-02...
I don't read enough French (especially at PhD thesis level!) to parse everything, but even I can see phrasings copied from the source documents in a lot of the examples. Some of them weren't even paraphrasing, they were lifting the exact distinctive word choices.
(Another one, unrelated, but also wild, argues that people who attack him are in fact against science itself, that they want to go back to the Middle Ages, etc.)
It's very obvious he pieced together interesting ideas from others to pass them as his own. And it worked very well, he has radio shows and TV shows and whatnot. And he still has a lot of supporters!
Also, being able to get ideas, synthesise them and present them in a way palatable for mainstream audiences is a useful skill and an important role in society. It’s just not research.
The article doesn’t really expand upon what having fragments copied from others means. Even if it fits the letter of the definition, on a phd thesis that may or may not be a big deal. If he’s passing off the ideas of others as his, or faking his research by using the results of others or making them up, then that’s really bad. If he’s just using phrases / wording from others to get his original points across, it looks bad but I don’t see it as a huge deal, especially 30 years out from the phd.
A PhD is supposed to be original research, if the originality or integrity is in question that’s one thing, the rest is much more pedantic, even if technically wrong.