Can't they simply hire the first eligible person? One can go through resumes and filter out people who don't meet objective criteria(e.g. work experience, location). This should be trivial. Then once they have 30 good resumes, they can call these people for interview. Assuming 10% chance of each candidate meeting the job requirements, they have >95% chance of finding a good candidate.
With automated resume pruning, it shouldn't take more than two hours for initial pruning. Actually, the higher number of applications means they can put in stricter pruning conditions, leading to lesser manual pruning later on. Assuming 2 hours/person interviewing, it should take less than a 40 hours-person to close a position.
I'd guess there's also some benefit w.r.t company loyalty when hiring a good-enough candidate instead of the best-available. They would be less likely to switch jobs compared to someone who can solve a leetcode hard problem in 15 minutes.