Windows 11 23H2 boots up successfully even with "Secure Boot->Disabled" in my BIOS - Is this normal?

As has already been mentioned, the Windows 11 requirement is that the system be capable of Secure Boot, not that it be enabled.

I have several cheap Mini PCs that report from the BIOS that they are capable of Secure Boot but there is actually no way to enable it in the BIOS! However, even those systems work flawlessly with Win 11 and setup never complains about those systems.

I have a different but related issue. When I was using a Acer system and used a VenToy USB Flash, there was a way to enroll the USB so it will boot up with SecureBoot enabled but on my Dell XPS 15 9570, there is no such option so I toggled Secure Boot off as my Windows 11 always booted with Secure Boot Mode on in Deployed but when I enabled it again, it keeps saying No Bootable Devices found but will boot up fine with Secure Boot Mode off or Secure Boot mode on in Audit mode so how would I even go about fixing it so it will boot up with Secure Boot Mode On in Deployed mode again. I noticed the only problem is I can no longer use Hyper-V as it requires Secure Boot Mode enabled. Windows Subsystem for Linux and Windows Subsystem for Android appears to work fine. So how would I get the certificate back onto the GPT UEFI partition so it would boot again?

I fixed the Secure Boot enabled in Deployed Mode issue, see How to fix this - Operating System Loader failed signature verification