This is a running theme for Blue Zones and centenarian research data, just a bunch of really blatant falsehoods packaged as trendy diet advice (e.g. suggesting that the Okinawan diet is low in meat, which is based on some weird game of telephone around discussions of WWII starvation diets, when in reality the Okinawans get a large proportion of their calories from lard and have the highest meat consumption in Japan). I wouldn't quite call it a "scam" but I would call it extremely misleading.