I never understand the point of the "But he was elected fairly" angle. So was Vladimir Putin as far as anyone can tell, so was Adolf Hitler, so was Stalin, the only major dictator of the last century that I can think of that definitely seized power through illegitimate means is Castro I suppose you could also make an argument for the CCP but certain people refute that.

Most dictators become dictators over time, the vast majority don't grab power from a legitimate government because they would instantly have a fight on their hands. Usually that only happens with the US's assistance.