Regarding MANRS, specifically, here’s a snippet of the article:
Implementing the MANRS recommendations, which are based on existing industry best practices, can have some short-term costs for ISPs, but according to ISOC, that’s probably not the reason why many of them have failed to implement them. The bigger problem, the organization believes, is a lack of awareness about these problems or not having the expertise to fix them.
The methods through which routing leaks and IP address spoofing can be dealt with are diverse and currently documented in different places across the Internet. That’s why ISOC and the MANRS members are working on a Best Current Operational Practices (BCOP) document that will bring those recommendations together and provide clear guidance for their implementation.
The goal is to assist the small, regional ISPs with adopting these measures, because they make up around 80 percent of the Internet, said Andrei Robachevsky, ISOC’s technology program manager.