We'd like to support the complete toolset, but given the scope of the work as compared to the number of contributions, we have to focus on specific use cases. For example, for fastboot, we've focused on the use case of flashing ROMs. Therefore, though this is a regression, I'm categorizing this as wishlist. Supporting the ext4 formatting feature in fastboot was a byproduct of our effort, and the removal of that feature from fastboot was entirely due to upstream code reorganization.
