I think people who make and collaborate on strategic technical decisions need up close and personal perspectives on in the trenches technical work. I think non-technical managers have a very hard time detecting when someone is blowing smoke. I think former engineers can turn into non-technical managers fairly easily if they aren't proactively contributing actual patches and reviews to their projects.
Collaborative, blame free technical culture is ideal, yes, but it requires technical leadership and some amount of technical strategy. Someone (or some committee I guess) has to be able to decide when a project costs more than it makes. Only someone technical can actually estimate the projects. You can collaborate in and delegate that estimation, but there still needs to be a decision somewhere.