Fortran isn't scary, but porting a system from one architecture to another, when that system includes Fortran, Assembly, Cobol and other parts IS scary, which makes emulation (and terminal scraping) a robust solution, and recompilation/porting an expensive one.
[And Fortran does have scary aspects: from the 25 year old hacker's test: "Did you ever change the value of 4? In a language other than Fortran?" - numeric literals in fortran aren't constant!]
I haven't seen many cross-platform issues with FORTRAN. (If you redefine 4 on any platform, it will be bad.) IMO, C is much more time consuming to port to a different platform due to system headers and inevitably different system APIs. POSIX helps, but certain parts of the system aren't covered by POSIX and so you wind up with #ifdef platform support where new support needs to be added.
> I haven't seen many cross-platform issues with FORTRAN.
Most fortran floating around is cross-platform fortran, and that is quite easy to port. However, legacy systems are usually very much platform dependent. I was once hired to port something in Fortran from a System 3090 (or was it 390? That would be more than 20 years ago now) to an SGI workstation, and it took several weeks of full time work.
And you're ignoring the subject under discussion: Porting a working system comprised of multiple parts in multiple languages (COBOL, Fortran, ASM, REXX, ....) is a much harder than the sum of porting individual programs - which is why emulation + terminal scraping is the cheaper, more robust solution.
[And Fortran does have scary aspects: from the 25 year old hacker's test: "Did you ever change the value of 4? In a language other than Fortran?" - numeric literals in fortran aren't constant!]