I'm perfectly happy to believe Chinese hardware is riddled with backdoors. What didn't make sense to me is why Bloomberg was so adamant about this claim but never provided a single shred of evidence in support of it. If someone proved this to them why don't they have a compromised board they can publish pictures of and give to a third party for examination?
Because they don't have the evidence or it's unobtainable (either too sensitive or doesn't exist).
If China really has a chip that can reprogram/modify server motherboard instructions with only 3 pins all within the size of a rice grain (according to Bloomberg's story), they've already won the tech war.