That doesn't sound like a bad matching algorithm, it's more like you found a bug on the search form: distance and sex are presumably filters in the query, not input to the matching algorithm. And it sounds like a rare bug too, since if a lot of people were getting results of the wrong sex that would quickly become an issue.
I may be being harsh, but the comment sounds like a troll to me; he's describing horrendous, show-stopper bugs like failure to respect basic search filtering criteria which the apparently large number of HN readers with accounts on OKC have failed to report. I don't find the post in any way credible.
