Marcel van der Veldt (@marcelveldt) in his excellent comment on a GitHub issue about Matter and Thread connectivity mentions that Matter 1.0 devices are really problematic and should be replaced. How do I determine the Matter version of a device?
The CSA-IOT (Matter certification authority) has a database of all certified products which lists what specification they were certified to. It’s not clear whether this is updated if/when the vendor issues firmware updates; presumably they would have to re-certify (which presumably requires $$), but you could use this for factoring into purchasing decisions if you wanted to.
As far as devices already commissioned to your fabric, I can’t confirm whether the specification version is part of the device’s BasicInformation data set, which can be viewed in the Matter web UI dashboard (port 5580 for non-HAOS users) under EndPoint0. I only have Tasmota Matter devices, which aren’t certified, so I don’t see a specificationVersion under BasicInformation. Maybe someone with more devices can see if there are, and whether they match the database?
I don’t see anything in any of my certified devices .