He did not call you a joke. Nor was he feeling the waters for permission for laughing at this matter.
Rather, he was trying to express that malice might not the culprit here. It is stupidity (or ignorance, laziness, etc). Please keep in mind that intelligent people can also be the most dangerously stupid people around, since they don’t even acknowledge it (I would like to stress that my comment is getting into abstract, and not meant as an attack or something. Rather a point of argument/debate/discussion).
And, if he did, then hey….. Wouldn’t be the first time I’m wrong.
…It is not that you need to act as the New Testament advises, turn your cheek, and respond as a Japanese Lawsons’ convenience store attendant. ….It’s so you do not make an ass out of yourself or belittle someone that did not deserve it…
(And, if you are curious, my ideal “ladylike” is not Victorian... I prefer feisty. …But he was not even as close to dismissive, so you are getting your slap on the wrist.)