As we enter this era of far more qualified candidates than jobs, HR will die eventually the equivalent of index funds is for hiring. Just as most money managers didn't beat the market and lost out to Bogle's low-cost index funds, people will figure out that HR doesn't do any better than any other random criteria for hiring and firing employees, since most of the applicants for most jobs will be able to do the job sufficiently well. Probably the answer is some sort of AI, but I bet you could do just as well rolling dice.
If most of us are honestly with ourselves, we'd realize the marginal return on difficult hiring decisions is extremely small.
As for the CYA aspect of HR, an AI can definitely do that cheaper and more callously.
I would have assumed hiring / screening resumes is a relatively small fraction of what an HR department does?