I think your rant is actually perfectly reasonable and justified. The ray traced render features in After Effects were originally marketed as a major new feature, and users were justifiably excited by them. True 3D built right into After Effects was a real game changer!
Sadly, because it's usability was hamstrung by being entirely hardware-specific to one brand of GPU technology, and even then required specific support to be written for each and every GPU, for which the poor AE engineers clearly weren't provided adequate engineering sources to support quickly, the whole project frustrated users enormously. Many users were horrified to discover their expensive new hardware wasn't supported, and the CPU rendering was so abominably slow that it was basically unusable. (I must confess I got a decent amount of work being hired by designers who had got themselves into trouble with AE ray trace render times and deadlines!) New Mac Pro users like yourself, who can't use NVIDEA GPUs, were one of the casualties.
As you've seen, third party solutions like the new C4D integration, or VCP Element or Zaxwerks 3D Invigorator/Pro Animator, are all useful tools but require substantial learning curves, and are always hamstrung by their external existence within the AE pipeline.
It's a shame Adobe couldn't develop the ray traced renderer more, but clearly it was just too much of a drain on their resources to continue extensive development. But I understand your anger that such a highly touted feature was so quickly thrown aside for an alternative.