They spun it to get him all bought in on it. But the truth is the slot is where you put your slow cover guy who has good physicality. They were stashing him at times there but calling it something else. Other times they were just cashing in on his physicality to supplement the run game, which was not a bad approach given it is such a strength of his.
But if he was still a shutdown corner they would have kept him outside the hash. You don't pay a slot corner what they were paying Ramsey. Hence the move.
Now it is possible some of that was him just being content and lazy. That maybe he comes in for Miami now with a chip on his shoulder and ready to compete. But I suspect he's going to get torched more this season and the Rams making that move will be looked at differently over time in the media.