Monitor zigbee utilization?

Nothing prebuilt but check out this new feature ZHA developers working on for zigpy-cli (which is available in Home Assistent) and links referenced there → Advanced energy scan by puddly · Pull Request #49 · zigpy/zigpy-cli · GitHub

Regardless read and follow all these best practice tips → Zigbee network optimization: a how-to guide for avoiding radio frequency interference + adding Zigbee Router devices (repeaters/extenders) to get a stable Zigbee network mesh with best possible range and coverage by fully utilizing Zigbee mesh networking