>>userbi+(OP)
I don't think I understand your threat model here. In the dystopian remote attestation future, presumably nobody's going to grant you access unless you're running Windows, at which point Microsoft can impose arbitrary policies without needing to involve Pluton at all (all it would do in this case is verify that you're running Windows, and you can already make that determination using a traditional TPM). So under what circumstances would you find yourself unable to gain access to a remote resource unless you're willing to accept a firmware update that changes Pluton's behaviour in a user-hostile way?