Anyone here with any literature / sessions one could go through for a good gist of things with respect to Blast Radius?
The recommendation you read was probably about limiting the blast radius. It's a general security best practice, and you implement it through techniques like federating (compartmentalizing) services away from each other, limited lifetime credentials, attribution, SSO for single point of control for invalidation of credentials, principle of least access (PoLA), privilege separation with role-based access control (RBAC), session logging/audit logging, etc. Most importantly the underlying system needs to have a well-defined and pentested authentication/authorization architecture. The hallmark of systems that limit the blast radius is that they have well-defined limits on how much they trust each other.
OWASP (https://owasp.org/) is a great starting point for reading about this stuff.
[1]: https://hn.algolia.com/?dateRange=pastYear&page=0&prefix=tru...