If it didn’t cap scaling (which it does now), it would eventually become more difficult than even heroic dungeons because you can overgear them.
Ideally for me, things would go something like:
Normal dungeon gear -> WQ gear -> Heroic dungeon gear-> LFR -> ??? for casuals, but right now it is just WQ/emissaries and warfronts. Normal dungeons are pointless, heroic dungeons are pointless, lfr is pointless other than seeing the raid… which is fine… but I am talking progression of character strength which doesn’t exist for casuals anymore it’s hit max level… do a few things… done. That is far from compelling gameplay.