“Kernel DMA Protection Indicator” effectively allows for OS-level DMA-remapping via IOMMU. Enabling this for Windows-based systems provides for “Memory Access Protection.”
It is important to note that not all device drivers support DMA-remapping.
Unless you specifically require security hardening due to physical access concerns to your machine, I recommend disabling this feature along with Pre-boot DMA Protection.
More from MS:
Kernel DMA Protection | Microsoft Learn