It is a pretty random example, but it is meant to say that the math is rarely the limiting factor for security. People spend time thinking about this type of stuff because they like it, not because it is actually important for security.

In my mind RSA is the last instance of a mathematical development changing the game of security. After that it is twists of the same idea on more obscure mathematical objects, and pyrotechnic protocols that only the truly unhinged (ethereum people) are willing to try out in practice.