This is not about being entirely unqualified.

My criticism here is that all you need to get this result is that there are some jobs that some groups apply to more than other groups despite being less qualified.

We know from other literature that men are much more likely to apply for jobs they are unqualified for, there could be other group differences, or there could be a bias of more men from a certain demographic applying for a job type than men from other demographics.

I don't know the answer, but there's a lot of ways for this sort of thing to show up when you look at data with a fine tooth comb and ask why its not perfectly even everywhere.

I'm sure we could have a whole separate argument about the disparate impact standard's validity for society (it is a matter of law ofc), but even if you accept that standard, I think you should be skeptical of the harms noted in this paper.