Perhaps the DPRK wouldn't be as poor and reclusive if they hadn't had almost all the cities in the north bombed until there was nothing left by Americans. And South Korea's situation was really not that great either for a long time. It was led by brutal US installed leaders like Singman Rhee. The north was much better off by most metrics until later on.
North Korea had higher standards of living than South Korea until the 1980s. Bombing hasn't really got anything to with how bad North Korean system is.
It's undeniable that the embargo is responsible for quite a lot of economic suffering in North Korea while only strengthening the Kim monarchy's grip.
It's also undeniable that the South Korean government eventually reformed their way out of fascism. Was that narrow, twisty, and decades long path worth the war that was fought, given it is also simply impossible to say what would have happened if the Allies had let the fascists in South Korea be conquered?
Would that have strengthened the Kims, or would they be more like the modern Vietnamese government? Or would they just have been annexed by the PRC?