someone told me the wifi blobs exist because of regulations prohibiting wifi chipsets from being easily modified to use illegal frequencies, but they still want to do much of the functionality in firmware so they can have more flexible asic designs that can keep up with standard changes. If that is all true, wifi blobs are unlikely to change.
Regulatory issues are one reason.
The second is that the wifi side of things might be some 3rd party IP they bought and the licencing terms prevent open sourcing it.
Wifi stacks are complex and filled with edgecases. And every release just makes that moat bigger.