Also, it never occurred to me that anyone would see the entire front half of the Death Star sunk into an ocean and think the tides would somehow be MOVING it. It’s not floating ON the water, and I can’t imagine the tides are so strong that it’s being pushed across the bottom of the sea floor, either.
The dagger is goofy and dumb, but to suggest it’s goofy and dumb because the Death Star would have moved in the meantime doesn’t really make any sense. It’s not like a lightweight piece of detritus. It’s the entire front half of a moon-sized battlestation. It’s not going anywhere because the tides are a little choppy.
It’s goofy and dumb because the dagger has no reason to exist. The tides are a very minor point. It seems like the wreckage would shift over time, due to a large part of it being flooded, but I suppose the dagger could have been made just a couple decades ago. But I’m still wondering who made it, and why they shaped it to match the skyline of the wreckage. It’s goofy and dumb because if Rey had been standing a bit closer to shore, or a few yards to the right, the dagger would have been useless.