From my point of view developing for FSX is as complicated as it was for FS9 from technical point of view. There are many developers that claims the materials and workflow are to complicated. It's not true. You can assign a color texture only, and it's exactly the same as it was in FS9. If you want transparency there is ONE difference. You have to click a button 'Set Default Transparent'. That's all. FSX is even simpler - you don't have to follow a strict naming from SDK.
FSX lacks another thing - script driven animations, for a 3d artist like me, keyframe animation only is an advantage.
Design standards - I agree with you at this point. Simulators are getting complicated. Most of users want in depth simulation of given aircraft, detailed external and VC, correctly working switches and gauges and this is the problem for hobbyists. Developing such plane takes much more time, and it's not easy to make a single person year long project. How many of you would like to fly a plane with single 512x512 texture, no VC, and few basic animations?
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