In residential places in Europe I‘ve seen this mostly in old buildings where the walls are stone/brick underneath, so I am assuming it would be hard to put the

In residential places in Europe I‘ve seen this mostly in old buildings where the walls are stone/brick underneath, so I am assuming it would be hard to put the cables inside walls? Also, this was always inside, not on the outside walls, plus the cables were laid in tubes fixed to the wall and painted over, so well enough protected, probably. Did you see issues with decay with this sort of installation even inside an appartment?