> The vast majority of CVEs are not exploitable, basically noise.
This is not true if you consider security-in-depth. Many of them are exploitable on their own but maybe not in combination with other issues that are as yet unknown or known but not patched everywhere.
As a simple example a local privilege escalation issue that is not exploitable on a device that only I ever have access to, essentially becomes a remote root access flaw if you have untrusted or unreliable users (clients with accounts for instance) on the system. This works on a finer grain too, seemingly minor issues spread through the kernel and user space can add up to a serious exploit.
This is the most common "not exploitable" CVE I have to deal with at work all the time. Things like buffer overruns when passing headers, but my server shouldn't be accessible to the public Internet anyway, and if it is, then we have much bigger problems. So yes it's technically exploitable IF other safeguards fail, but the reason it's irrelevant is that if those other safeguards fail, we are in deep shit anyway.