If you're familiar with the scope inheritance behavior of angular 1.x, that would basically be a reasonable model (i.e. setProtoTypeOf on props objects down the chain). That would avoid people taking the shortcut of doing {...spreadProps} when they have to pass a lot of properties to many small child components, and let you distinguish locally passed props vs inherited props during debugging.
IsolatedComponents wouldn't inherit props from their parents. The idea of an IsolatedComponent would be to present a boundary on inherited props. That would give you the simplicity of the old context api, but with more fine-grained control over how it is propagated (hopefully leading to fewer foot gun moments).
IsolatedComponents wouldn't inherit props from their parents. The idea of an IsolatedComponent would be to present a boundary on inherited props. That would give you the simplicity of the old context api, but with more fine-grained control over how it is propagated (hopefully leading to fewer foot gun moments).