King Hussein is not a dictator by virtue of being a hereditary monarch.
...and an autocratic ruler.
Furthermore, the Soviet premiers that came after Brezhnev were the heads of non-democratic governments but I'm not sure I'd call them dictators. Andropov, Chernenko and Gorbachev didn't seize power.
Nor did Stalin neither the successive presidents of the Argentinian military Junta after Videla. Seizing power is not what define a dictator. Furthermore, Sandinistas seized power from Somoza, the dictator of Nicaragua. By no means you can define Daniel Ortega as a dictator in the 80's, neither he is a dictatorial ruler in the present day, regardless corruption and several shenanigans. Anyway, this poll is indeed a joke including the man who abolished army in Costa Rica and excluding the most relevant dictators in the 20th century: Hitler, Mussolini, Stalin and Mao.