@LimeJellyHead, ah we are probably more in agreement than we first thought, then.
I was still a child in the 70s but I am aware of the history of dieting. Calorie counting in the 60s, then low fat in the 70s as though it was going to solve all the world's problems. Then low carb, Atkins, etc. Then sugar was poison. Then paleo, warrior diets, fasting and back to calorie counting again by a younger generation that thinks they invented calories. Round and round it goes.
As for my personal opinion, I do think the low fat aspect of SW is a bit dated. I also agree with points of view that the food manufacturing industry absolutely loved (and still loves) low fat ideologies because it allowed them to make 'diet' versions of all their foods where the fat was replaced with sugar and sweeteners. The advantage being that low-fat 'diet' foods are far cheaper to manufacture than the higher fat versions. I would agree with you as well that we are having an unprecedented diabetes problem in the West and this is largely attributable to people's insulin levels spiking because of too much sugar / sweeteners as well as general obesity.
However. Even though I think the low-fat aspect of the SW ideology is a bit out of date, in my view, where it succeeds is that people don't actually realise how many calories are contained in oil and fat. If they did realise, they would cut back a bit. Avocados - all good, natural fat but could be up to 300 calories each. For me, that's a lot because my total daily energy expenditure is only 1,500. In order to lose weight, I have to shave 500 calories off that amount, meaning that a large avocado is nearly a whole meal. Or take olive oil - I have nothing against olive oil at all and would rather use that than some synthetic alternative. But when I have only 1,000 calories per day to 'spend', it's valuable to me to know that 1 tablespoon of olive oil is 120 calories. That really makes a difference to how much oil I will use when cooking or even if I want to use it at all.
For me, the main value of SW is weekly motivation. I'm about to nip down there now and see if I have won Slimmer of the Week again. The main thing that gets the pounds off for me is watching calories, of which I'm a lot more careful than I used to be. And the 16:8 IF has helped terrifically with reducing my calorie intake. I don't snack. I don't graze all around the clock. I have two meals a day, one at about 12:30 and the other one in the early evening which absolutely must be over by 8:30pm no matter what. I'm usually not too hungry for the second meal and I'm amazed how much IF has shrunk my appetite.
Using a mix of all these methods, I've lost 20 lbs in ten weeks. I plan to drop another 15 pounds between now and Xmas and then I'm done and I can spend the rest of my life doing maintenance.
It was fun speaking with you! Always interesting to compare strategies.