So anywho I'm not sure why Samgoog would bother with such a high resolution display just to make a half assed "has more pixels" feature check.
The whole point of the "Retina" idea is that the pixels are no longer visible, at average viewing distances. That being the case, it seems unlikely that the screen of this hypothetical tablet would look any better than the iPad. So for no actual improvement in perceptible performance, you're getting the overhead of having to push that many more pixels, with the concomitant demands on battery life and the CPU.
So they can claim a somewhat higher spec for that one metric while necessarily ceding thinner, lighter, longer use and fluidity for the UI. Unless Samsung has secrete super tech that they've been holding onto, or expect everything else to advance to meet this proposed screen.
When Apple does this, they do it with a firm roadmap in mind, and compelling reasons. Retina is as good a resolution as is required, so they move their devices to that as soon as possible, even when they know the first iteration may suffer slightly in other areas (as in the case of the current iPad). For Apple, that screen is sufficiently compelling (and given that for touch devices the screen is pretty much the whole deal) that it trumps higher power demands. Hence, the new iPad is very slightly heavier and thicker than the model is replaces (to accommodate a larger battery), while maintaining similar battery life. Now that they have the pieces in place, they will commence to iterate that design, so that while retaining the Retina screen it gets faster, thinner and lighter. Apple will have once migrated everything to what they consider the best possible user experience and go from there.
That's such a different way of proceeding than deciding to "compete" with Apple by trumping their Retina sales point. All that does is give you all the overhead headaches without a clear reason or path forward. Like everything else Apple does, their design choices are integrated into the whole process and customer experience, over multiple years and device models. It seems like all Samsung can glean from that is that they should have a bullet point that matches every single thing that Apple does. Trouble being it starts to kind of pile up at some point and become unwieldy, if that's your only reason for doing things and you don't have a larger plan that puts the customer first.