Downvoter, you haven't read the damn article

Fil-C has some limitations. Presently, it only works on Linux/x86_64. Also, it's slow – about 1.5x-5x slower than legacy C. That's in part because of its implementation of a pointer encoding method for tracking bounds and types called MonoCaps, and also overhead from calling conventions and dynamic linking that differ from standard C.

This is the definition of Worse C, and nobody wants nor need that