I think you presented the list very well. Several points have been touched on already, I will mention one: DSL. I agree that the perception of it as a barrier

I think you presented the list very well. Several points have been touched on already, I will mention one: DSL. I agree that the perception of it as a barrier to entry in a project may exist. I think it is as incorrect as tying Lisp to AI, albeit for a very different reason. Indeed, a new member of a team has to learn DSL if one is used in the project. However, new members always have to learn the conventions and patterns used in the project they are joining. DSL makes some of them explicit and more understandable.