Which Anglo-Saxon attitude, lol? My relatives from London and Surrey do NOT have a very open attitude about Northern accents, I can assure you! My sil and bil, and others in the family would be totally unable, or rather unwilling to understand a strong Scouser or Geordie, let alone a Brummie! (Liverpool, Newcastle and Birmingham), I can assure you
BTW there are so many very strong regional accents in France. And here in CH, a trained ear will quickly and clearly identify a Neuchatel from a Vaud, a Fribourg from a Valais or Genevan accent. I live near the Neuchatel / French Franche-Comté border, and the Franche-Comté (dept 25 Pontarlier) is just as strong and slow as Neuchatel, but with a totally different emphasis- hilarious.