I've had Williams/Ceci 2014 quoted at me before and it was hugely over-generalised then too. There's simply no rational basis for claiming (like you implied) that it shows wide-spread discrimination against men. It's a study of tenure-track hiring for four STEM subjects, one of which showed zero bias.
> The drop out rates for males are (much) higher.
Seems off-topic, can you explain the relevence of this? There are serious problems with boys education but they don't seem to have a problem with discrimination in the workplace, see [0][1][2][3][4].
> ... simply because of an attribute that should not significantly factor into the decision.
That's an opinion I think there's reasonable evidence to discard, or at least add some nuance to.
Diverse workplaces are more pleasant to work in, and in the case of universities it seems reasonable to believe (based on the work of Carol Dweck & others) that having relevant female role models would improve outcomes for female students in STEM subjects.
Additionally there's a growing body of evidence that documents how diverse workplaces have higher productivity; and gender gaps in entrepreneurship negatively affect GDP (Cuberes & Teignier for a 2015 example http://www.economist.com/news/americas/21661804-gender-equal...)
[0] Female students seen as less competent than identical male students with identical application materials, offered lower starting salaries (Moss-Racusin et al, 2012)
[1] People in gender-incongruent roles penalised more heavily for mistakes (Brescoll, Dawson, & Uhlmann, 2010).
[2] Voluble women perceived as less competent and less suitable leaders, inverse true for men (Brescoll, 2011).
[3] Women who succeed in male-dominated fields percieved as not likeable (Heilman et al, 2004).
[4] Students question the competence of female teachers who evaluate them negatively, less so than male teachers (Sinclair & Kunda 2000).