FYI, by default the ZHA integration just creates entities in Home Assistant for device features and functions that are standard in the official ZCL (Zigbee Cluster Library) specification, and therefor custom ZHA Device Handlers (zha-quirks) are generally only needed if the device firmware have some manufacturer specific functionality (e.g. features and functions) that is not standard in the ZCL specification, or if the device firmware has implemented ZCL specification incorrectly (i.e. poorly written firmware or a bug in the firmware).
You and all users in the community can still help the ZHA developers by reporting specific device bugs and custom device support requests as issues to their zha-device-handlers repo on GitHub:
So by definition all Zigbee devices that do not use manufacturer specific functionality should be compatible with the ZHA integration out-of-the-box without changes, and if they do have manufacturer specific functionality then the ZHA integration should only need a device handler to expose those specific quirks that are unique to that device or manufacturer.
For more detailed explaination also see:
Hence manufacturers needs to provide complete documentation so ZHA developers can add support (and provide firmware updates if needed).