It is telling that nanoleaf knows about the matter issues and yet has not released a firmware for the essentials products since September...
Makes it look like they really don't give a ■■■■ about the matter issues.
My other (non-nanoleaf) matter devices have been working fine though, I'm happy to say.
So Matter the "universal solution" is (at the moment) no better than Zigbee and Z-Wave with regard to adhering to standard.
But I'm finding the connections more stable than pre-matter. Probably because I can now pair everything with its most optimum hub and have them bridge or share.
One thing I noticed with the Kasa switches and plugs.
@kkossev wrote an advanced matter outlet driver and I am using that for the plugs. I was using the generic matter switch driver from Hubitat for the switches.
Whenever the switches went offline it took a lot of messing around to get them back online. When the outlets go offline which is much less, the advanced driver has a few cool buttons that bring them back online without any fuss and also has way more connection info built into the driver.
One interesting thing I've discovered with my Nanoleaf bulbs is that any bulbs that are in the same room as the associated TBR are very reliable.
The bulb that is one floor above the TBR often becomes unresponsive.
Been tempted to connect that one to the ST TBR in the same room and see if it makes any difference.
An alternative approach could be to start building a strong Thread mesh by adding other mains-powered Thread devices. The EVE Energy Smart Plug is a good choice, in my opinion.
I've heard they were good, but wow, those are pricey; $55-$60 each here.
Eventually, replacing both Zigbee and Zwave meshes with a Thread mesh is the way to go. Although I am not sure we're there yet, as the selection of Thread devices is pretty limited for now.
@jbaruch I don't see a reason to replace the stable working Zigbee/Z-wave devices... The new Thread devices are still to prove their reliability.
@bradford.clarke - the prices in the EU are the same as in Canada... Unfortunately, the new Thread gadgets are more expensive if compared to the same functionality Zigbee models.
I'm very curious about the new Aqara Boarder Router Smart Plug and how it might be able to integrate into certain setups. The Eve's can only be a certain distance away from a boarder router; otherwise, they will not work (similar to Zigbee). However, Aqara's new device is also a boarder router, which means it could create it's own thread system but still be connected via Matter to other controllers. Granted, it's not available yet, but I could see it be valuable in certain setups depending on the cost.
At some point, you'll have to choose; I mean, how many smart plugs of different protocols do you need? 
And if Thread fulfills his promise, I'll be the first one to ditch all my Zigbee and Z-wave crap. I don't enjoy tinkering with any of it (well, I do, to an extent).
Absolutely with you there. As I mentioned, eventually, but we're not there yet.
Funny, I have WiFi, Bluetooth, Zigbee, Zwave and Thread devices. The only crap devices I have are Thread (read Matter).
Obligatory xkcd
On paper Thread is much better protocol than zwave or zigbee.
That assumes the extra complexity doesn't exacerbate communications between units of diff mfg.
KISS seems to never be wrong.
Z-wave does have one particular property that sets it apart - it's a lower frequency signal that can penetrate walls etc better than Zigbee or thread. However if you have good wifi coverage at 2.4GHz all over the property, and it's not too swamped, you don't need that.
".... not too swamped" is a big "if" with those of us that still have land lines, blue tooth devices, kitchen appliances, TVs etc all in the same band, even if Matter works fine, causing other things to fail is just as bad.
That makes me wonder. Last week I wondered if I could have multiple HomeKits? One I’ve the bulbs is right next to a AppleTv, but it is not the one I have HomeKit set up on.
I generally find “on paper” and “actually” to be two completely different realities.
"In theory, there is no difference between theory and practice. In practice, there is."
Their devices were originally developed on Matter 1.1 (or maybe 1.0) (and an earlier version of openthread). They are currently beta testing a Matter 1.2 firmware, with the updated openthread SDK and it seems to be a significant improvement.
To get the beta firmware, follow the instruction here: https://helpdesk.nanoleaf.me/en-US/how-do-i-sign-up-for-beta-software-updates-for-my-nanoleaf-lights-341522
Download the Hubitat app
