Yes, any newer Silicon Labs EmberZNet and Texas Instruments Z-Stack based Zigbee Coordinator does support it, (and note that not even the new ConBee III adapter support “install code” as of yet)
Personally I recommed buying a USB dongle/stick format Zigbee Coordinator so that you can connect it via a USB extnsion cable for better placement to get it away from any sources of interference, see → Zigbee networks: how to guide for avoiding interference + optimizing using Zigbee Router devices (repeaters/extenders) to get best possible range and coverage
That is not true, there needs to be support for it in the firmware and API for it needs to be documented.
So it is true older Zigbee Coordinator SoC chip as older Zigbee stack running on those do not support “install code” (or “qr code”), and even if they did then they also need to provide API documentation on how to use it via their serial interface. There is a summery explaination of this under “Limitations” in ZHA docs:
https://www.home-assistant.io/integrations/zha#limitations
Support for commissioning Zigbee 3.0 devices via “Install Code” or “QR Code” via the ‘zha.permit’ service has so far only been implemented for ‘ezsp’ (Silicon Labs EmberZNet) or ‘znp’ (Texas Instruments) radio type in ZHA. Other radio types are missing support in their respective radio libraries for zigpy or manufacturer’s firmware commands/APIs.
FYI, there is more information about Bosch BTH-RA (a.k.a. Smart Thermostat 2) in this other thread → Bosch Thermostat 2