There's not much Kernel Level malware singed in Windows (drivers have more scrutiny for whatever that's worth). Regardless, the point is that companies using KLA rely on the relative difficulty of circumventing protections implemented in a signed kernel, running signed drivers, on a machine where there is some chain of trust.

You don't need to take my word for it, Tim Sweeney said it himself (using dirty innuendos and weasel words, but anyway). EAC supports Linux, but doesn't utilise KLA (for many reasons), and doesn't make the same claims about protection as it does on Windows.