I think it's important to distinguish between application layer and lower layers of the stack here. For the lower layers (firmware updates for protocol changes

I think it's important to distinguish between application layer and lower layers of the stack here. For the lower layers (firmware updates for protocol changes notwithstanding) it is basically all federated, as you say. But at the application layer there are protocols that you can participate in just by knowing the protocol, and others which require knowing a secret or getting included in trusted peers or otherwise filtered to effectively make them proprietary and not federated.