My Matter (and Zigbee, and Z-Wave) hub is a laptop I paid 300.00 for almost 10 years ago, when I wanted something cheap for the semi truck.
I run Home Assistant on it now. I have both a $40 zwave USB stick, and a similarly priced Zigbee stick.
The software for the hub comes with HA. Just install the matter server
Their zbt-1 dongle can do either zigbee or thread, but matter does not technically need anything else. Thread does, but not Matter. Install Matter Server addon and you can use any matter WiFi device.
Correct. Unlike zigbee and zwave Matter does not define a single communication technique.
It can be used with thread, or over a standard ~~tco~~ TCP IP network.
Typically, Matter devices will support either thread or WiFi, but there's no definite distinction to Matter itself.
If you also want to use Matter over Thread devices, you will need a thread dongle. The ZBT-1 can do either thread OR zigbee but not both at once.
In fact, the biggest issue I see with Matter is that there's no real easy way to tell if the device uses WiFi or thread.
There are a lot of Matter devices out there now, but only a few use the Thread protocol.