I think you hit the nail on the head here and probably why so many engineering jobs are gained through personal referrals instead of cold resumes. I know that's how I got hired at most of the companies I've worked at.

The company I work at building a way to capture those recommendations and that concept of trust through peer-to-peer reviews: https://www.roikoi.com/

The site asks you to play a anonymously game comparing your most relevant coworkers to one another and a users' score is generated by their aggregate results from their coworkers playing the game. It essentially crowdsources gauging those qualities that can't be gathered from a resume.