I wouldn’t be to sure about this. The matter specs don’t obligate to expose pretty basic features like “power on state”, “detach mode” and others (like OTA update) which means vendors can put this in their walled gardens and force the usage of their app and cloud infrastructure (including obligating to register with personal identifying information like mail or phone). 
In a nutshell matter is the continuation of Zigbee and doesn’t allow full ownership and often only limited local control 