Hue is super-reliable for most people. Easily one of the best Zigbee implementations out there. Most likely, 2.4 GHz WiFi channels (or Thread channels) are overlapping with your Hue Zigbee channel.

https://www.oscium.com/training/zigbee-wifi-coexistence/

Deploying 2.4GHz Wifi, Zigbee, and Thread near each other requires some planning + corresponding configuration. A lot of Zigbee hubs try to find a quiet channel during the initial setup, but it does not always work.

How does Zigbee compare to Matter?

Matter over Thread is the most comparable to Zigbee (there is also Matter over WiFi). It's vastly more complex, since it uses IPv6 (ULE), mDNS, non-radio links between TBRs, provisioning is typically done through a smartphone with Bluetooth LE [1] etc. But it's also more standardized in that Matter defines the device types, so in principle a device will work with any Matter server, whereas with Zigbee support generally needs to be added per device (though there are generic drivers as well).

Big tech and IoT companies love Matter, because they can eventually gather analytics from devices or require cloud subscriptions. This is not just the case with Matter over WiFi, but Matter over Thread already allows devices to use NAT64 to connect to IPv4 servers on the internet (and TBRs like Apple TV do not allow you to disable NAT64). Thread 1.4 also allows for Thread devices to get globally routable IPv6 addresses. The Thread 1.4 white paper does not even try to hide what this could be used for:

Thread devices can now seamlessly connect directly to cloud services, enabling remote control, monitoring, and over-the-air firmware updates.

https://www.threadgroup.org/Portals/0/Documents/Thread_1.4_F...

So, yeah, Matter + Thread does some things better, some things worse, and opens up new avenues for monetization that were not possible with Zigbee, because Zigbee devices were fully local and owned.

[1] There are workarounds, e.g. Home Assistant allows provisioning through Bluetooth proxies. Also, provisioning does not currently work on alternative ROMs like GrapheneOS.