MKL, macOS, and GNU Fortran

Intel MKL Gurus,

A quick question: why is GNU Fortran not an accepted compiler for MKL on macOS?

(1264) $ $MKLROOT/tools/mkl_link_tool --os=mac -libs --compiler=gnu_f --parallel=no

       Intel(R) Math Kernel Library (Intel(R) MKL) Link Tool v4.4
       ==========================================================

Not supported compiler for current configuration:gnu_f. Supported values for compiler: intel_c|intel_f|gnu_c|clang|pgi_f|pgi_c

Configuration
=============

OS:                     mac
Architecture:           intel64
Compiler:               gnu_f
Linking:                dynamic
Interface layer:        lp64
Parallel:               no
OpenMP library:         iomp5

I'm sure there is a good reason, but as I use GNU Fortran a lot on my Macbook (hey, free compiler) and MKL is free(-ish) at least for my experimenting/fiddling so it would be a nice option to use if I could.

Thanks,

Matt