A common use case for secure boot is when I want to use my device however I want to while being reasonably confident that I'm not letting 3rd parties use my dev

A common use case for secure boot is when I want to use my device however I want to while being reasonably confident that I'm not letting 3rd parties use my device however they want. Especially if you have a device that stores information that might be sensitive (user passwords, encryption keys, bitcoin wallet, safe combinations, thermostat settings, whatever).