FORTH has one serious problem. Like your friend said, "Not everyone can handle" it. In organizations that hire programmers based on buzzword compliance and cost, it's only natural all FORTH code would be rewritten in something more... popular. It's true FORTH successes are most visible in not very visible niches. There was a time every Sun and Apple computer came with a FORTH interpreter in ROM and most SPARC-based servers probably still do.
It is a beautiful language, if you can handle it.