A little history courtesy of Wikipedia: the Roman historian Livy praised the white wines of Limoux in ancient Rome, which were not yet sparkling; indeed, since Livy, "vins de lumière" referred to still, fine and fruity whites. From that era throughout the Middle Ages, it was observed in Italy and France that some wines occasionally became spontaneously sparkling. This phenomenon was reportedly noticed at Limoux in the 16th century by Benedictine monks from the Abbey of Saint-Hilaire, which would make the Blanquette de Limoux the oldest sparkling wine in the world.
"Ancestral" because this is the original method for sparkling wine: simply bottling before alcoholic fermentation is complete. You probably know that grape fermentation produces alcohol and CO₂.
Of course, these are natural sparkling wines: neither filtered nor clarified, with no additives in the winemaking, just grape juice. Roger's idea is already making its own way, and new collaborations are emerging between other winegrowers. That too is the philosophy of natural wine.