[pantalaimon]

Why do you need Encryption for security? A signature should be enough.

(Don’t conflate security with confidentiality)

[agustamir]

Not in the context of enabling trusted binaries being used for updates, but to your original point about reverse engineering unencrypted firmware

[pantalaimon]

It's not common for firmware to be encrypted, just as it's not common for executables on your PC to be encrypted.