I don't think it would be particularly useful. The most common usage of seccomp is hardening an existing sandbox by reducing kernel attack surface. Fine-grained

I don't think it would be particularly useful. The most common usage of seccomp is hardening an existing sandbox by reducing kernel attack surface. Fine-grained control is crucial for that, since it's the entire point. Every unnecessary system call or permitted system call flag is added attack surface. When seccomp is actually being used to implement the sandbox semantics, the application usually needs to be designed around it. It's very difficult to apply it this way to an existing application. I just don't think there's a strong use case for coarse control when it's so far from being the real hard problem.