Graphics add nothing except cost and primarily serve to placate people who enjoy shiny objects. Immersion is a state of mind, graphical quality has no influence in that. If you can't get immersed, its because you have no interest in it, but because your game doesn't push enough polygons.
Now, since you're question is could a game like Minecraft with high res crap be good, yes, it could. However, the processing demand would be ridiculous, the development times and costs would be astronomical, and the game would either look very odd as it tried to retain a "blocky" aesthetic or it would take obscene amounts of time due to how small the pieces you'd be forced to work with would be to retain a "high res" look, and I still would bet money that the depth and freedom of the game would be very restricted compared to MC. Not to mention I don't see how it would be doable in a first-person point of view due to the size and volume of components one would need to "build" with extremely small polygons. Honestly, the more I think about it, I don't think it would work or else you'd be spending days to build a high-res brick rather than a big blocky building.
Now, since you're question is could a game like Minecraft with high res crap be good, yes, it could. However, the processing demand would be ridiculous, the development times and costs would be astronomical, and the game would either look very odd as it tried to retain a "blocky" aesthetic or it would take obscene amounts of time due to how small the pieces you'd be forced to work with would be to retain a "high res" look, and I still would bet money that the depth and freedom of the game would be very restricted compared to MC. Not to mention I don't see how it would be doable in a first-person point of view due to the size and volume of components one would need to "build" with extremely small polygons. Honestly, the more I think about it, I don't think it would work or else you'd be spending days to build a high-res brick rather than a big blocky building.