From an systems perspective they are the same thing. Zigbee vs. Thread is just transport. The protocol on top of that is what matters and the sole purpose (from

From an systems perspective they are the same thing. Zigbee vs. Thread is just transport. The protocol on top of that is what matters and the sole purpose (from my narrow perspective) of Thread+Matter was that this would be a team effort to allow different vendors to talk to eachother. And with that in mind IPv6 feels like a decent choice. If vendors don't respect that foundation then the whole point of Matter+Thread is just gone.