What I'm more interested in is what/where will Desmond be? If there is no hatch to cause the plane to crash, that means that Kelvin Inman never found Desmond on the beach. So does that mean Desmond still shipwrecked on the island is has been stranded there for the last three years, living alone in the jungle like Russo? Has he met Russo and been living with her? Was he caught by the others and is with them now? We know he is in the show, so he wasn't killed by the smoke monster.
Or, by destroying the hatch, does that somehow prevent Desmond from ever shipwrecking on the island in the first place?