Lora Keys (AppEui, DevEui, AppKey) modification with Downlinks

Dear TTN community!

I am looking for good practices regarding the device capability for reconfiguration using downlinks.
Shall LoRa specific parameters such as AppEui, DevEui, AppKey be reconfigurable with downlink messages?

In theory AppEui, DevEui and AppKey should not change across the product life-time, but do you see any use case where such modification might have been required?

What about other parameters for example enabling/disabling the ADR or changing the Channel Mask? Would those parameters reconfiguration over the air make sense?