There is little point in talking about exact weights of different kits or dynamic range comparisons. An M camera and lens are smaller than a D800 and an equivalent lens, no way around it. With a smaller lens, and a smaller body, it feels pretty different carrying it on your shoulder compared with a D800 and a comparable lens, even if the weight doesn't seem dramatically different on paper. On the other hand, with the 35mm 1.4 comparison he mentions, that's something you're going to feel in your hand. Ignoring that would be like saying a D4 is essentially the same as a D800.
I'm not a big Leica fan because it doesn't suit my shooting style, but for some people, they work well. There's really nothing else out there quite like them (not an X-Pro1, not an X-100s, etc.), and it doesn't have to do with resolution or dynamic range measurements. It's more analogous to why some people on this forum like photographing with F3's or F2's - it's a different shooting experience and a feel and way of working that appeals to them. That Leicas don't really appeal to me much doesn't matter; what matters is what appeals to those who enjoy using them. If you see the Leica solely as a prestige item, you're not one of the people who should buy one. Admittedly, there are a set of people out there like that, but there also some very fine photographers who use them for valid reasons.
As for on-line bloggers you don't like, my advice would be to move on and read the ones you enjoy.