Do you mean Thread or do you use Matter over Wi-Fi?

I use both, but preferably matter over thread when it makes sense (as wifi just uses so much more energy).

Thread over Matter is not fully local. In Thread < 1.4, devices can connect to internet servers through NAT64. Most Thread Border Routers (AFAIR Home Assistant + OTBR is the main exception) do not allow you to disable NAT64.

In Thread >= 1.4, devices can request globally routable IPv6 addresses. The Thread 1.4 white paper does not hide the intentions:

The Thread 1.4 Border Router acts as the IPv6 router between the Thread network and external networks, including the user's home network and the larger internet. It is by default configured to support external communication [...]

Cloud Connectivity: Direct internet connectivity enables Thread devices to easily connect to cloud services. This facilitates remote monitoring, control, and firmware updates, enhancing the user experience and enabling remote device management capabilities. Device vendors can now directly service and support their deployed fleet of devices, regardless of which application ecosystem each device is integrated with.

https://threadgroup.org/Portals/0/Documents/Thread_1.4_Featu...

This is what you get when you let Google, Amazon, Apple, and Samsung design a smart home standard. They'll use every opportunity extract analytics and increase control. You'll own nothing and be happy.

Zigbee, Z-Wave, and ESPHome over WiFi/Thread are the only major modern local and privacy-preserving smart home standards.

But matter is a better network. More efficient and faster. Large zigbee networks with cheap devices often result in ghost devices not responding. Matter even with the cheapest 2 dollar bulbs from AliExpress have zero issues.

Matter is not the network layer. You are either talking about Thread (which uses IEEE 802.15.4 like Zigbee) or WiFi. Matter is the application layer protocol.

We have a lot of devices and never have any issues. But yeah, if you put a lot of Tuya Zigbee devices with crappy firmware that flood the network. Similarly if you put a lot of crappy WiFi devices on your network, it's a security nightmare (wise people put them on an isolated VLAN and use WiFi client isolation).

[delayed]

That’s not the case at all. Matter over thread is newer. The latest range of ikea smart home stuff is all thread.

Thread has the advantage of consuming very low power so battery powered sensors and remotes can run for years. Wifi is only used because it doesn’t require buying a thread border router.

> AFAIR Home Assistant + OTBR is the main exception

Luckily this is my setup.

I am not opposed to the possibility of cloud connectivity (as long as it is deactivateable) and even if I weren't I think I still prefer Matter (thread/wifi) over nearly all non-matter devices I've ever used, especially all the problems I had with Zigbee devices will make me stay far away from it. (Even though I am aware that many people had gread experiences with zigbee.)

I think this interpretation is a bit too negative. Undoubtedly the companies want to spy on you, and with Thread 1.3 they were already perfectly capable of doing so - via your Thread border router, which connects to the normal LAN and can talk to the Internet (if you let it). Allocating Thread devices from global IPv6 blocks (GUAs) doesn't change that, it just removes the NAT between Thread devices and the border router.

Before Thread 1.4 the IPv6 addresses used by the Thread network were all ULAs - i.e. the devices were only routable locally and didn't have a global IPv6 address, so if you did happen to want to talk to your Thread devices over the internet, it was possible but the Thread border router had to do NAT for you.

With Thread 1.4 the border router can assign device IPs straight from the global IPv6 block assigned by your ISP, which means you can directly access your Thread device over the internet without the NAT provided by the Thread border router. If you don't want to locally host your smart home automations (you and I do, but the average consumer doesn't) this can be very useful.

IMO this fits perfectly with the philosophy of IPv6 - every device can have a globally routable IP address without needing NAT.

If you don't want your devices reaching out to the Internet (like I don't), the solution is to put all that stuff on its own VLAN with no Internet access (which I do).