You're absolutely right. A Leica M-series camera is built like a tank. Built to the same standard as a Nikon F-series cameras. These are bodies built to pro standards, ready for the most abuse you can throw at them. If that's what the user needs, that's absolutely what s/he should get. And for anyone who wants the joy of owning such a precison built piece of equipment, go for it!
On the other hand, Nikon recognized 40 years ago that there are amateur users who would like the same features as the ones pros had on their cameras - or most of the features - but didn't need a camera built to the same standard because either they wouldn't put it to the same kind of use or didn't require quite the same level of precision. These are enthusiasts who still seek the fine art of photography in their spare time that pros make a living at.
IMHO, the Zeiss Ikon is the camera that Leica should have built. It fills the same niche that Nikon filled for decades with the N8008/F801, N/F90, F100. As good as these cameras were, they weren't an F4, F5, or F6. But they did everything that any amateur could want, they were well built, & they were embraced by many pros for a variety of reasons. Leica has eschewed this opportunity. Seeing their potential cusomers buy on the used market did nothing for their corporate balance sheet.
The Zeiss Ikon & the Hexar RF before it mean that the consumer doesn't have to settle for the choice of Leica or the short base line of a Bessa. It's nice to have greater choices.