Generic tangents always make threads less interesting, because they take attention away from the specifics of what's new in an article and direct it instead to one of the large pre-existing topics that people tend to fixate on. I sometimes compare this to a spacecraft flying too close to a black hole and getting sucked in: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que....
It was flamebait in two ways: (1) Generic tangents on inflammatory topics are already flamebait; and (2) the comment makes a huge assumption (that the previous situation was "racism / sexism") and treats that as fact without substantiating it. Large unsubstantiated claims about inflammatory topics are also flamebait.