Recruiting is Broken

There are actually a lot of startups out there solving the problems that you mentioned.

Try entelo or sourcing.io if you want to free yourself from retained search and search on your own.

They've actually done a great job aggregating millions of developers based on their social profiles.

If you want to hire someone based on their skills not credentials, hackerrank is definitely a way to go.

But of course, they are not perfect either if you're looking for specific language skills.

Hackerrank does a good job of picking out candidates who are strong at cs fundamentals in my opinion.