That is your personal view and most developers see it exactly the other way around.

And what I mean with one platform: When working with a node editor I dont care about DirectX, OpenGL, HLSL, CG and so on. My algorithm works on all these platforms. Basically shaders are nothing like that, a couple of vertex and pixel operations and I dont see why a node based shader should have such a big performance difference. If that would be true, no professional engine would use it. UDK / Unreal as an example is very fast that way. So actually, without any testings I would not claim something like that.

There is for sure a difference, but I would not overestimate it hat much. I read such arguments often. C4 programmers as an example defend their C++ language at all costs. They always tell it is the best, fastest and whatever. But in reality I saw games programmed in Java as an example running big FPS worlds with huge terrains and interiors (Chrome as an example). Often people are too much focused on their tools instead on the final product that could be done with other tools as well.