The knee jerk reaction to secure boot-anything from the technical community has been generally "No!", "It's a trap" etc.
E.g. the FOSS community wasn't a fan of only-trusted-secure-boot when it was microsoft holding the keys and the source and releasing neither.
Secure boot isn't a technical solution to a soft/firmware update problem. It's a control mechanism to solve a management problem. Crazy idea, don't put the interface that has access to firmware on the standard interface. Use its own interface and allow motherboard manufacturers to support it for enterprise/datacenter geared systems.