That video was more than 20 years ago, mate. Please. He already said a thousand times that he evolved and changed his mind, seeing the democracy as the ideal system. But I'm sure you didn't saw these videos, 'cause you seems to watch just what the media shows to you. And no, he is not a threat to democracy because of what he thinks about the militar regime. That happened in the Cold War, and a lot of countries suffered and made dictactorships at that time because of the ideology war (argentina, chile, uruguai, brasil, panamá, cuba, vietnam, north-korea, hungary, romania, albania, afeganistan, Czechoslovakia and a lot more). But this is another topic.
The real threat is a government that supports and send money to ACTUAL and CONTEMPORARY dictatorships, like Venezuela, Cuba, Angola and more. The real threat is a party that has in the government plan the "regulation of the media". Why? So they can send money just to those who support them? I don't trust anyone to regulate the media, and you should do not trust too. Also, they want the "Social control" of the legislative, executive and judiciary. Not satisfied, they want the "Social control" over the public ministry too. This is totalitarian and a REAL threat to the democracy.
But you'll say "oh but this means that the society will have voice in the government". No, 'cause this "social control" will be executed by the people THEY will choose. You and me will have no voice. This is exactly what happened in Venezuela, search it, it's not conspiracy theory. Their constituent assembly was made with the politicians and "social groups", all of them chosen by the government, so they can have, in a "democratic" way, the majority of the votes to do whatever they want to.
I do not even made metion to the corruption of the PT, used to buy votes inside the congress, to finance election campaigns, to finance they're associates and themselves. This, my friend, is also a threat to democracy. Or do you think it's okay to buy the Congress and approve whatever they want to? Anyways, my vote is Bolsonaro. Good luck.