Entities can be identified via their entity-id. I consider this a technical name (as opposed to the display/friendly name). The technical name should never change since a change would break automations, scripts, UIs and …
For devices there is only the name. If you change it, a dangerous dialog pops up asking to change the device’s entities. You normally don’t want that.
The request is, to introduce a device-id, next to the device’s name. The former would rarely change, and if the admin wants to change it, the entity-ids should be adapted accordingly.
This request also responds to several forum questions regarding naming convention. One op even recommended to first change the device name into a technical name (allowing the entity-ids to be adapted), then changing the device name into the display name (not allowing entities to be adapted). I think, this hints the problem.