Is it really a far comparison? Apple has a proper bootloader capable of secure booting 3rd party OSs. What part of the open-source ecosystem was built different

Is it really a far comparison? Apple has a proper bootloader capable of secure booting 3rd party OSs. What part of the open-source ecosystem was built differently? It just so happened that after possibly even more painstaking reverse engineering, the responsible hardware vendor later realized that server machines are de facto linux, and they better support it properly. Like, that Intel chip working that good was not achieved differently, we just like to wear rose-tinted glasses.