Another feature that was introduced to Windows — one that has contributed to the decline of rootkits — is DSE (Driver Signature Verification a.k.a Code Integrity verification) for drivers that basically checks that a driver is signed by a trusted certificate authority before loading it.
DSE makes it even harder for attackers to load a driver, as they would have to bypass this mitigation too — either by getting their hands on such a certificate, which they could use to sign their driver, or by exploiting the mechanism in such a way that would bypass it.
An example of a Patch Guard+DSE bypass can be found here.
There are also some older Digital Signing Enforcement/Code Integrity bypasses by hfiref0x, such as DSEFix and TDL (Turla Driver Loader).