The title of my post is conjecture, but I believe the process through which I arrived at the conclusion is sound.
In this tier, you can gear up through dungeons and be ready for this tier of raids. I often complain about the "forced" nature of daily quest rep grinds, but the truth is it's possible to raid without doing any of them (obviously that is far from optimal).
When the next tier of raids is released, the 463 rewards you can get from dungeons will not be sufficient for running that tier. We won't be forced to gear up in Tier 14 before Tier 15, as that model of progression has been retired since WotLK. We'll either get a new set of dungeons with tons of higher ilvl gear, or we'll get currency from dungeons to buy the appropriate gear to start the new raid tier. Dungeons have always been a source for pre-raid gearing, and this will continue to be the case throughout the life of the expansion.
If ALL pre-raid gear for the next raid tier is locked behind rep grinds, this would be a monumental shift in design philosophy from Blizzard, and I don't believe they can afford to risk that big of a change. Therefore, to me the conclusion is self-evident: we can expect better rewards from dungeon grinding in our future. Sorry daily quests, but you won't have a monopoly on pre-raid epics forever.