A NUC is overkill for PiHole. You can run it happily in a VM assigned less resources than an equivalent Pi Zero.
I don’t run anything on the bare metal NUC directly. They’re all VMs (or Docker containers running in a VM) running in ESXi, with appropriate resources allocated (in the case of PiHole, as you say, those resources are pretty minimal).
I didn’t mean to imply running PiHole on an entire NUC.