I just hope they aren't simply thinking they can sell the game based on nostalgia. Too often these days studios try to use loopholes to continue selling games before buckling down and offering a truly worthy experience. Bungie themselves come to mind especially as of late.
With Halo 4 getting the story mostly right, and Halo 5 getting the multiplayer mostly right, you would have to hope they can put both together now and end up with the full package. If Halo Infinite does have it all, plus this new engine, it would be a massive system seller for new XB hardware.