While experts believe the displayed canisters are merely design concepts, and not actual working missiles
You guys should go watch some frontline shows on this topic, North Korea has grocery stores and electronics stores and clothing stores etc that are fully stocked and you are not allowed to actually buy any of it. They are for propaganda, news stories pretending the Nation is prosperous and normal people have freedoms and access to good things when in reality they do not. Sure there are some “rich” areas where people so get a lot of access to stuff, but they are an extremely tiny segment of the population.
So one can easily say everything in North Korea is about (fake) appearances. Those “missiles” are not real, they are display pieces and nothing more.