edit: why doesn't this have a parent comment anymore? bug?
Giving someone a coding exercise is the most time and cost effective way to filter people. Why waste time spending eng or HR hours calling someone when they can't code? As dumb as it sounds, giving a simple assignment probably culls the number of actually applicants down significantly.
job searching is already tedious, demoralizing and requires a lot of time on the applicant. stuff like immediately shows no empathy for the people applying for jobs or respect for their time. like i said below somewhere, i guess the filter works. i can't imagine anyone worth their time is playing games like that