Now, note what I said that started this thread, that you can do FP in any language. I never said you could do it well or maintainably. For some languages (I am thinking of Java in particular, but C++ seems similar there), I can't imagine it being more than useful as an academic exercise.

Certainly there are languages which don't support FP approaches well. But lack of utility is not the same as impossibility. If nothing else the exercise ("How far can you take FP in Java?") will teach you all kinds of things.