I overheard a conversation recently in which one person repeated the oft-heard discounting of the Paleo Diet: "It's not real, you know, they don't know what people ate a long time ago." And, actually, that is not the truest critique of the Paleo Diet, for we do know something of what people ate long ago, just ask Dr. Michael Eades who writes about the science of identifying "caveman diets" on his blog and discusses it thoroughly in this video. The most legitimate critique is that our modern foodstuffs just mimic rather than duplicate what our ancestors ate. I'd have to agree with you, if that is your critique of Paleo.
But, I'd say, there goes the baby and the bathwater, because the Paleo Diet is actually an excellent tool. I use it in my practice as a clearing tool: go off grains, legumes, and dairy for a month and see what happens to your chronic health problems. With most folks, we can re-introduce some or all of the omitted foods, but the month has been invaluable on many levels. Eat differently and intentionally for a month, it will change your relationship with food. If, in particular, you also eliminate foods that cause inflammation and irritation (gluten, other grains), irritable bowel and addictive behavior (dairy) and interfere with other nutrient absorption (legumes), you just might also eliminate a nagging health problem of any sort. Every Paleo-friendly doc has seen depression, arthritis, psoriasis, irritable bowel and more shrink or disappear over those thirty days.
Staying on the Paleo Diet longer is very useful if you have metabolic syndrome or type 2 diabetes, a finding that has been noted several times and was just described in this review study. Comparing a Paleo Diet (characterized as low carb, high unsaturated fat and low saturated fat) to a diet corresponding to conventional medical advice (low fat and high carb), the Paleo Diet performed equally well in weight loss, slightly better in compliance, and significantly better in the most important diabetic markers. Blood sugar control and cardiovascular markers improved more with the Paleo Diet than with the conventional diet.
In my book, that counts as real!