Quote Originally Posted by dr bob
Not quite. More like survival of the "most convenient".
But that supposes that the 35mm SLR is the "most convenient". Personally I find the typical 35mm SLR big, heavy, unwieldy (lens heavy), intrusive, and noisey. They are a kind of "one size fits all", but its pretty hard to find something for which the typical modern 35mm SLR is the BEST solution.

If 100 years ago Kodak could build a small, lightweight, 120 camera at an entry level price, why can't we have that option now? Where are the rangefinders, the TLR's, the waist level finders, the choice of film formats... Most of these designs should be cheaper to produce that the complex mechanism that is required in an SLR. However to get any of these features in a new camera you need to step well outside the beginers budget, and you won't find them even in many so-called specialist camera shops.