This may explain a little. This map of the regional languages has been around in one form or another for decades. First, it's languages, not dialects of French, and not régional accents. So if you are listening for French, this isn’t it.
Interestingly, these regional languages were heavily suppressed for decades but are now studied by both scholars and regionalists, along with movements to save the languages and traditions. By the time I named my first child in the late 1970s, the suppression was lifted and the Brittany version of my child’s name was accepted. It hadn’t been previously.
Second, when I first lived in France in the early 1970s, and visited farmers in Burgundy, not far from Beaune to be precise, I couldn't understand any of them. Those R /r/ rolled like a Cuban cigars right on the front of the tongue, among other things. OTOH, I could understand my hosts, though they were born and raised in the same area, because they had lost their accents as butchers in Paris--rue Cler post war until 1970.
Third, the accents have changed tremendously in the past fifty years. We watched a film by Agnes Varda on Kanopy the other night, “Daguerreotype”, filmed in the early 1970s on the rue Daguerre in Paris, in which she interviews shopkeepers who came to Paris post war. All came from the same area, Brittany to Laval, but the differences in accents between the older people and the younger was remarkable.
Until we saw this film, we had forgotten about those old countryside accents because we just don't hear them anymore, except the occasional bachelor shepherd or very rural farmer. And my in-laws, originally from very rural areas of France, had lost their regional accents by the time I joined the family in the 1970s.
So the map is languages, not accents. Accents have moved toward standardization. And, some people are trying to keep the regional languages and traditions alive.