1. what counts as functional programming (and more specifically "why lang X is not really functional")
2. inventing new jargon, particularly in cases where existing terminology is mostly adequate, but some hair-splitting detail is not properly covered by a word already in use. this tendency might be a natural consequence of spending all day on macro expansions.
It's like someone saying to a scientist, "that's just a theory, man."
Even that's not precise. What mathematicians call computable functions, programmers call total, pure functions, and even then only as an approximation.
It always disappoints me when I read such things; it turns FP into a moving goalpost or a mirage. If you really like FP and want it to be more widely adopted, an approach of encouragement, "steps in the right direction", etc. will do more good than "holier than thou" scorn.
I've tried to follow this attitude when e.g. discussing on HN and answering on Stack Overflow; I wrote up some of my longer FP descriptions into a blog post at http://chriswarbo.net/blog/2015-01-18-learning_functional_pr...
[1] https://xkcd.com/thing-explainer/
[2] http://splasho.com/upgoer5/phpspellcheck/dictionaries/1000.d...
Funny, but OO people did something like that too.
2. inventing new jargon, particularly in cases where existing terminology is mostly adequate
Many programmers are guilty of this, particularly if they are young. Once you've been around a few decades, you start seeing this pattern.