It actually is, because the interview process influences the size, diversity, and caliber of the pool of candidates who apply to your organization, complete the interview loop and accept offers.
If you have an unlimited engineering budget or a big, attractive name then by all means, force candidates to jump through as many hoops as you'd like, you'll still be able to fill open reqs. But the majority of companies are not in that position and in fact struggle to attract and retain technical talent.