To play a bit of devil's advocate, I don't think the problem is necessarily with the compiler output. It's more that it's not always easy to definitively state the precise consequences of a particular issue, especially when it comes to memory safety-/UB-related issues. For example, consider this Project Zero writeup about using a single NUL byte buffer overflow as part of a root privilege exploit [0] despite some skepticism about whether that overflow was actually exploitable.

To be fair, I'm not saying that Greg KH is definitely wrong; I'm only willing to claim that in the general case observing crashes due to corrupted pointers does not necessarily mean that there's no ability to actually exploit said corruption. Actual exploitability will depend on other factors as well, and I'm far from knowledgeable enough to say anything on the matter.

[0]: https://projectzero.google/2014/08/the-poisoned-nul-byte-201...