It is a different story if they asked in good faith, but they clearly started their initial comment as a derisive declaration of something being useless, so it sounded to me that they had no real intention of actually learning.

You may want to follow the thread where we continue to discuss it in good faith. I think they’re sincerely inquisitive, and sincere (and impressively candid!) in expressing their understanding gap.

I think the various “assume best intent” rules and adages would benefit greatly from a huge “assume limited familiarity when dismissiveness seems out of place” addendum. At least for technical topics where the stakes are “whoops we actually just disagree on the merits”.