industrial control and enterprise networks

That's doing a lot of work here.

Yes, it's important in certain situations, but for consumer devices, it's just another thing that can go wrong when using alternative operating systems. Regular users don't have the physical risk these other systems do, and making it more difficult for users to install more secure operating systems goes against the bigger threat.

Linux is compatible with Secure Boot (source: I exclusively run Linux, and use Secure Boot on my systems), but some distros or manufacturers screw it up. For example, Google Pixel devices warn you about alternative ROMs on boot, and this makes GrapheneOS look like sketchy software, when it's really just AOSP with security patches on top (i.e. more secure than what ships with the device). The boot is still secure, it's just that the signature doesn't match what the phone is looking for.

It's just FUD on consumer devices, but it's totally valid in other contexts. If I was running a data center or enterprise, you bet I'd make sure everything was protected with secure boot. But if I run into any problems on personal devices, I'm turning it off. Context matters.