It makes sense that higher levels of complaining would correlate with lower levels of sexism. Things don't usually get fixed unless people complain.

Could be more the other way around: in a really Xist field, there are fewer complaints because a) there are probably fewer [minority group] to complain, b) complaining feels riskier and less likely to achieve anything, c) complaints that do get made are more likely to be quickly shut down rather than amplified.

The rise in complaining has not been correlated with a drop in "sexism", even the kind that is a bit of a stretch.