Locked bootloader still allows sideloading unsigned OTA's

``` Device: Pixel 10 OS: crDroid 12.11 ``` Hey there, not sure if it's avbroot's fault or crDroid's fault, but recovery allowed me to flash an unsigned, stock crDroid update. I got disoriented and accidentally applied it. Though, when rebooting the phone, i got totally locked out of it, giving me an error, something in the words of "No valid operating system could be found." with code: 5, after that i got the usual "Your phone is corrupt and cannot be trusted.". Forcing me to reset the phone, since i couldn't even reboot to recovery to sideload my signed update! (Luckily i had a full phone backup, phew.) Is it intended that it allowed me to sideload an unsigned update? Or is it crDroid's recovery's fault?