In this case the question would be, do citizens in a democracy have the right to dissolve their government peaceably, provided they meet whatever threshold is required in that system (Could be a super majority, for the sake of argument)? I’d argue it must be or it’s not really a democracy.
They have the "right" to have a revolution too - many countries treasure the revolutions they had. They can amend the constitution and make another democracy. They can also amend the constitution and make a dictatorship. Or just have a dictatorship without bothering. Those do not need constitutions at all.
To have a vote that turns a democracy into a non-democracy is a meta-democratic vote, not a democratic vote. Abusing a democratic system to surreptitiously make a non-democratic system is just a caveat that dictators find convenient to use.
A dictator is just someone with absolute power. How he got the power is orthogonal. He doesn’t have to gain power through insurrection or a revolution, he can gain it inside a democratic system. In fact in Ancient Rome, where the term comes from, the Dictator was appointed by congress in times of crisis.
Indeed, dictators are dictators, including all those in your examples. In the cases I brought up, an elected leader can turn into a dictator by not leaving when they lose an election, canceling regular elections, faking the vote totals, etc. One Person, One Vote, One Time.
