For anyone wondering: AF_ALG is a Linux socket interface that exposes the kernel’s crypto API via file descriptors, using normal read(2)/write(2) calls for hashing and encryption.
So the options related to AF_ALG have always been disabled, because I have not encountered an application that needs them, among those that I use.
Unfortunately the Linux distributions must enable in their default configuration most options, because they cannot predict what their users will need.