Once again, you're confusing materials and manufacturing complexity for actual mechanical complexity. I remember when I first got a close look at a jet turbine fan blade, and being puzzled by some aspects of it, like the channels that ran all the way through it. (I remember thinking that those channels must have been pretty tricky to make.) But then I realized that these were probably for cooling, like you said. I was most impressed by its relatively complex shape, and by no doubt the exotic material that it was made of and the tight tolerances it held. But in the end it's nothing more than a simple fan blade.
BTW, I had some similar impressions about the close-up look I once got of a large rocket engine nozzle. Then I realized that it was really nothing more than a big coiled cooling tube surrounded by an external shell - pretty simple stuff, actually. And the "de Laval" part of that nozzle, which is what makes it work to begin with, is as simple as can be and is a design which dates back to over a century ago.
I know that it's a big container holding a bunch of fan blades on the same rod that push air around at different speeds.
But from what I found, the Trent 1000 (Rolls Royce engine for Boeing Dreamliner/787) cost $8B to develop and has 30,000 components in it. I just don't agree with you that the elegance of it's mechanism of action means that it's not insanely complicated in its implementation.
And that component count no doubt includes very basic things like rivets and nuts and bolts and wires and connectors and so on. Maybe even the individual balls in the ball bearings, if they still even use such things. Probably also the individual electrical components in the control circuits and such. And how many individual fan blades are in them these days - hundreds, thousands maybe?
Note the attached link; strip away all of the external pipes and wires and such (all part of the component count, no doubt), and what you're left with is mechanically relatively simple. A challenge to build and maintain, maybe, with tons of fan blades, but still pretty simple.
BTW, I had some similar impressions about the close-up look I once got of a large rocket engine nozzle. Then I realized that it was really nothing more than a big coiled cooling tube surrounded by an external shell - pretty simple stuff, actually. And the "de Laval" part of that nozzle, which is what makes it work to begin with, is as simple as can be and is a design which dates back to over a century ago.