Yeah, they figure the Surface Book 2 is basically just an upgrade, not an overhaul, of the product.
They claim their "not recommended" rating is based on their evidence that 25% of Surface customers reported serious hardware-related problems with the systems -- breakage, dead, hangs, random shutdowns, crashes, etc. -- within the first two years of ownership. Microsoft's response was that Consumer Reports didn't appreciate the product's appeal to the customers.
Personally I think Microsoft's design is based on the assumption that folks will want to buy a new one every few years. It's not all that different from Apple's philosophy, actually. Apple makes their money off the hardware sales, so they have to move physical product on a regular basis. Microsoft tried the same thing with Surface.
Yep - it's a disposable world we live in today - I'm typing on a 7 year old computer with Win 7, my cell phone is 2-1/2 years old, and my wife says some of my clothes are older than our marriage of 26 years (I do have a Unit jacket, from the 2917th ESC, that is 40 years old from when I was stationed in Italy).
Ironic that many of the folks that always have the latest and greatest technologies are also on the Dole....