Generally speaking, local privilege escalation is not a problem for old infrastructure machines, because those machines don't run any third-party untrusted code.
To me it seems that a patch would be like trying to put a band-aid on the brainstem for a concussion. These exploits run lower and can be triggered at any time with the appropriate instructions. Is it even possible to patch?
Looks like this feature has to at least be enabled somewhere for it to work (it just so happens that for some systems it is enabled by default). If that really is the case it might be possible to disable the system, as long as only something in layer 0 can turn it back on. Although yeah still not an ideal situation.
Thanks for the clarification, good it's not on by default