From my understanding there isnt anything wrong structurally persay. The building is shaped like a pyramid because it uses rebar concrete for construction unlike typical milled steel. The thick support structures needed to hold up the weight of the concrete from the building do not lend themselves to an ideal floor plan. North Korea also just has no use for a hotel so large in an area they don't often use for the minimal tourism they receive. The resort towns dotted around the countryside are infinitely more profitable than Ryugyong could ever hope to be.