Without endorsing this specific idea, I think maybe after over half a century of C that this argument shouldn't get in the way of a new standard. Pretty much every other language has managed to solve this problem, and the people who write new projects in C/C++ have decided they're not concerned about buffer overflows, so if someone decides to start a new project using something like this (or go out of their way to add support for it to an existing project), that's kind of on them. The rest of computing shouldn't get stuck in 1972 forever.