My understanding is DPDK has much smaller set a supported nic's since it doesn't use the kernel drivers for the card along with all the other things that the kernel provides.

Wireguard in kernel gives great performance while just working if your kernel is already working on the hardware. Wireguard is so small it is considered easy to audit so is a prime candidate for kernel implementation.

DPDK is listed as an "Exotic" todo for Wireguard:

https://www.wireguard.com/todo/