This is extremely interesting. Thanks for this work.

"psychological safety is only relevant in teams where members actively collaborate on tasks (i.e. high interdependence)"

Indeed, the Agile community makes assumptions about the level of collaboration that needs to occur in software development teams - assuming that collaboration is much more than it actually is or needs to be.

Most of programming is solitary. Collaboration is crucial, but only at points. Collaboration needs to occur as needed, promptly, and then be followed by long periods of solitary work.

Also, psychological safety is an outcome of other behaviors, so it might be hard to separate it as its own trait or behavior. Psychological safety largely results from leaders who set the expectation that people can and should share ideas openly, and the leaders then support that behavior.