I'm using the terminology in a confusing way. Thread and Zigbee are both protocols on top of 802.15.4, but to be fair to myself there is a really common tendency to refer to "bare" 802.15.4 as Zigbee mostly because of the history. Zigbee is a very "thin" protocol though compared to Thread which is a lot more ambitious, but at the same time Zigbee goes more into application space... which kind of makes the point that Thread and Matter are a lot more "detailed" than Zigbee, which is minimalistic to the degree that interoperability of Zigbee products has always been very poor. This is one of the major reasons that Z-Wave mostly replaced Zigbee in the "smart home" space. It standardizes more functionality that Zigbee does. Thread and particularly Matter, in turn, standardize even more than Z-Wave (e.g. many of the things that are Z-wave config "mystery registers" that vary between manufacturers are included in Matter specs).