Women are genetically wired to seek out the best male to mate with. In a community that would generally be the leader, or someone who shows leadership traits. A bombastic individual is generally loud and aggressive and forthright which are are characteristics that can be seen as leadership traits. Hence they are attractive as potential mates.

That doesn't mean that they actually ARE good mates, of course. But for a woman looking for someone to provide for and protect her and her children it's a good place to start. Certainly better than choosing a misfit or weakling. Though if your social standing in the community is low then those may be your only choices. This is why social status in the tribe is so important and explains why niggers, for example, are so obsessed with clothing, jewelry, and other outward appearances of status.