I disagree that cryptography engineers understood viscerally how good a target RNGs were or how viable a PKRNG would be (further evidence for that would be the contortions attackers have to go through to extract enough wire state from Dual EC to mount the most straightforward attacks). I think you can formulate an argument that any major cryptographic primitive is the "lynchpin", and indeed you see people doing that, for instance with the SIMON/SPECK block cipher designs --- block ciphers, after all, are the lynchpin of secure systems.
I agree, obviously, that RSA added Dual EC because DOD demanded it. But most of RSA's revenue didn't come from BSAFE, or even things that relied on BSAFE. They were a crappy token company that bought RSA, then built a bunch of multi-factor authentication stuff that had more to do with IP reputation than with cryptography.
I don't really buy that anybody working inside RSA was absolutely convinced that Dual EC was a backdoor. I sort of don't buy that anyone was really even seriously paying attention. I think people think of RSA as a cryptography company, but that is not at all what RSA was at the time this happened.
None of this matters, really. We arrive at the same place about RSA's culpability. But if you came to HN hoping to find someone to stick up for RSA's decision here, you haven't been paying attention to the tenor of this place. All you're going to get here is hair splitting; that's the interesting conversation we can actually have. There's no viable debate about whether adopting Dual EC was defensible. Even when I was saying I doubted Dual EC was a backdoor, I still didn't think using it was defensible.