The more probable answer is that the NSA asked for the backdoor to be left in. They do all the time, it’s public knowledge at this point. AMD and Intel chips have the requisite backdoors by design, and so does Apple. The Chinese and Russian designed chips using the same architecture models, do not. Hmmmm… They have other backdoors of course.

It’s all about security theatre for the public but decrypted data for large organizational consumption.