Coding challenges and HackerRank

I am typically not a fan of coding challenges as a part of tech companies' recruitment processes, as I think they're pretty off-putting for high-value/top-quality candidates. But I never thought about Hackerrank or coding challenges as more than just a means to disqualify the obviously bad engineers. After reading this article, my opinions have changed on some points and remained the same on others: 

Pros: 

• HR and other bootcamps/coding programs seems to have increased the pool of employable engineers. I have spent my entire career recruiting for elite and small tech companies but never considered places like financial institutions and banks that "need to fill so many programming jobs that elite schools can't possibly pump out enough candidates". 
• HackerRank has given the VERY small pool of "Gregory Furlong"s the opportunity to join elite start-ups that otherwise wouldn't have hired him based on his resume. In most cases, I think poor resumes are indicative of what would be a weak coding performance but for the 1ish% of top engineers who are self-taught, HR allows them to be recognized when their resumes would have likely been thrown out upon first glance. 

Cons: 

• When used as part of the interview process, these challenges tend to be off-putting and a waste of time for top engineers (I think they can say "we don't have time to speak with you unless you pass this test")
• They tend to slow down an already lengthy recruitment process (sending a challenge and then waiting for it to be returned can sometimes take weeks)
• Although I mention this gives the top 1ish % of engineers the opportunity to work at an elite software company, the majority of self-taught/bootcamp engineers are still too weak to work in these environments