Not plaything - that's the big stamp on the big desk - but playground; the stage on which he struts and blusters and demands applause. He's not interested in running anything except more campaigns, which is akin to a theatrical tour. He didn't want the job of president, just the title and trappings and privileges.
How many other ways have you examined closely? Sure, it's quite common for demented and/or evil men to become boss of some powerful organization (nations, churches, corporations), but hey all have some agenda, some notion of getting real work done. Trump, and maybe a couple of the later Roman emperors and French kings, have no such aspiration. He would say "Apres moi, le deluge," if someone translated it for him - so don't!
You'e waiting for WWIII. Fair enough.As far as I can tell, he hasn't actually broken the world yet. At least, no more than anyone else has.
But he's put a few dents in the USA that won't soon be hammered out; inflicted a few scars that will never heal.
IFIf it does turn out that the overgrown toddler school of national and international government and diplomacy was as good as any other, then I guess we could conclude that the US doesn't actually need a president. Or it doesn't matter if they have one or not. Or it doesn't matter what he does or doesn't do.