The RPi zero 2 is nowhere near powerful enough to be used for multiple purposes as any of the above machines.
It could probably run a single-task relatively well, like PiHole or something, but otherwise it's in a completely different performance category. Like an order of magnitude.
So 6W idle for J5005 would put it on the same level of efficiency.
You're right, the RPi zero 2's CPU is slower - but that doesn't matter for non-interactive tasks. I don't care that my cloud backup export cron job runs 5 minutes (or hours) longer on the Pi than on a Nuc; I only care it happens daily. For the CPU-/GPU-heavy workloads, the RPi Zero W is works as an orchestrator for the > 10W computer: powering it on and off as needed.
It could probably run a single-task relatively well, like PiHole or something, but otherwise it's in a completely different performance category. Like an order of magnitude.
So 6W idle for J5005 would put it on the same level of efficiency.