Longevity is not the only factor of interest.
There's CR and CR. A paleo lifestyle will greatly increase natural tolerance to fasting, leading to longer periods without meals, up to one day at times. Deliberate CR is something different.
CR doesn't show up among blue zones or the world's oldest people. Rather, the opposite - enjoyment of life.
I read a chimp study that showed CR chimps lived longer but had terrible quality of life compared to the fat happy sly contented ad libitum eaters. That suggests it's a tradeoff between living longer slowly and living faster richly.
Longevity is extremely hard to study in humans and there are many better-established effects on health from altering biological inputs than anything related to longevity.
Most importantly, cages and unnatural diets may tend to exaggerate the positive effects of CR on animals. Now interestingly, many humans live in the modern equivalent of cages and eat highly unnatural diets...
Therefore, I reject your thesis that rejecting CR and pursuing supplementation is misguided.
I read a chimp study that showed CR chimps lived longer but had terrible quality of life compared to the fat happy sly contented ad libitum eaters. That suggests it's a tradeoff between living longer slowly and living faster richly.
Or living at all: http://junkfoodscience.blogspot.com/2009/07/calorie-restrictive-eating-for-longer.html