There is a grain of truth.
But then "a grain of truth" is as essential an ingredient to any
effective "Big Lie" as brazenness or outrageousness.
The grain of truth is that most IBM Midrange programmers have a tendency
to learn one or two languages, and then attempt to use those languages
for EVERYTHING, whether they're good choices for a given project or not.
It's the old "if all you have is a hammer, everything looks like a nail"
Programmers should become fluent in as many different languages as
possible. I realized that before I was halfway through my Freshman year
at the University; that's why, when I walked away with my sheepskin, I
also walked away with at least rudimentary fluency in Pascal, PL/I,
Lisp, PDP-11 assembler, and COBOL, as well as adding a few more dialects
of BASIC and FORTRAN to the ones I'd learned in high school. And as a
result, teaching myself C was relatively easy, as were MI, Smalltalk,
and Java, when I began working for Touchtone, and RPG, CL, and HTML were
downright trivial exercises.
If more programmers saw the advantage of having a wide variety of
languages at their disposal, then maybe IBM might have brought more
languages into ILE, instead of demoting them from LP to PRPQ (and
eventually dropping them entirely), and grafting so many other-language
characteristics onto RPG that it began to look like the results of a
drunk biologist playing with flatworms.
And likewise, outside the Midrange world, we wouldn't be seeing C used
for so much that it's ill-suited for, both system code that ought to
have been written in assembler, and application code that should have
been written in a true HLL.