Reading into that article, it looks like the NSA made a random-number generation algorithm standard, but upon inspection by cryptographers it was seen to be sus

Reading into that article, it looks like the NSA made a random-number generation algorithm standard, but upon inspection by cryptographers it was seen to be suspect due to its unclear origin of particular constants, and this was discovered as soon as the standards were published [0]. It was also slow compared to other standards, and as a result it was never widely adopted. By contrast, I can't find any significant security criticisms about Signal's double-ratchet algorithm, nor anything that would suggest that some sort of bad actor is pushing it to become standard. It seems to me like it was widely adopted because it's a solid end-to-end encryption algorithm. I also couldn't find where the algorithm was developed. If you have any sources for this I'd be glad to read it. [0] https://www.wired.com/2007/11/securitymatters-1115/ https://www.wired.com/2007/11/securitymatters-1115/