I would class an escape route as a designated communal escape route used by anyone trying to exit a building, as the regulations were brought in as a direct response to fire persons been killed using these communal routes and getting tangled in the cables then I suspect the regulations don't carry over to domestic.
If it was for all the exit routes from dorm's, houses flats etc then I would have thought a blanket regulation to ensure all wiring is fixed in this way.
This is an opinion so subject to discussion but when you know why the reg was introduced you can have an educated guess to what is meant by an escape route... I'm currently helping design mill complex with flats and the main communal routes are all been fixed on tray with steel wraps down the stone stair well and supported regularly with all round band above any corridor etc but the flats are wired as normal.