The developers of SciPy are maintaining a codebase that is 18% fortran, according to [1]. The only language that makes up a larger part of the codebase is python.
Don't you think it's possible their opinion on fortran is actually informed by quite a bit of experience?
This is also reflected by the following comment at https://github.com/scipy/scipy/issues/18118#issuecomment-155...
> The real maintenance burden is the compilation and the packaging not the code itself that we are carrying around.
The central issue is that their experience with the old Fortran doesn't translate to modern Fortran; they are two different beasts.
This is so true! I hope anyone could spend a few minutes checking what modern Fortran is before blaming it. A good reference is https://fortran-lang.org/en/