english usage aside: you could accuse him of handwaving, but he's not complaining, so his comment is not "handwringing". you are complaining (about his comment) so your comment is closer to handwringing.
"find a better user agent" is not handwringing; "i can't find a better user agent" is handwringing.
"find a better user agent" is not handwringing; "i can't find a better user agent" is handwringing.