In academic research it is especially important, and made more difficult by the complexity of the subject matter. The most successful researchers can succinctly explain their work (problem, significance, methodology and findings) to a layman. That's how you get funding. This also applies to startup founders seeking investors.
I'd say the above comment is about average, to average+ for hn... so probably not? (Only being partially sarcastic)
[edit: I now realize that that's not enough data, we'd also need how long it takes to write the average hn comment, and how long op took writing his :-) ]
It sounds like good practice in concise communication.