Name one instance that approaches this level of immaturity.
"Norway has become a shithouse country, actually"
Not a head of state, but I nominate:
Vladimir Volfovich Zhirinovsky (Владимир Вольфович Жириновский), "Russia's Trump"
So, yes, he was a thuggish populist troll, and I agree that his mode of operation was often comparable to that of Trump. But he never had power, and never came close to getting it.
For that reason, I think most would see Trump as being in a completely different league.