I think true -1x devs are also rare like 10x devs. To be -1x everything you "contribute" has to be a net negative. They are out there, but I think they're also rare.
I don't think so at all. It's really, really easy to slow down a team. The most common -1x behavior I've encountered is committing code that breaks something else, poorly executed "refactoring", misunderstanding the requirements of a task, and asking too many questions.
I've worked with -1x developers and have been one myself. I'm sure lots of other people here have committed these infractions at some point or another. But consistent offenders end up working on low-importance silo projects.
We all do that stuff from time to time, but I rarely find someone who is consistently that bad in everything they do. I have seen them, but my point is they are also rare.
