You have to consider how such situations come about.
They come about because a people are sometimes stupid enough to support these malevolent dictators enough for them to come to power. They don’t just appear out of nowhere like a James Bond villain. Malevolent people vote them in and they emerge from the group of malevolent people in the first place. With an armed people, these malevolent people are going to be the ones with the guns. And of course with every popular movement in one direction, another pulls back in the other direction, who will also have guns in a well-armed populace.
Then what do you think will happen? They turn on one another.
Without well-armed citizens, we get what we saw in Nazi Germany. With well-armed citizens we get what we see today in the Middle East. Have you seen the piles of rubble that used to be towns and cities over there? Either way, human life is decimated, and with well-armed citizens you get the added bonus of destroying all the things as well as all the people. Coming back from that, if you ever do, after undoing everything everyone worked for is no easy task - you might as well travel back in time, but with added emotional scaring from knowing what you lost and how you lost it. This fantasy that guns are going to protect you or anyone is just deluded. Its in the interests of government to avoid such a lose-lose situation, but if enough people vote it in, who knows what stupidity those in power will resort to.
Arming everyone, like in ancient times, was abandoned in favour of voting in a monopoly on violence for a reason. That’s how we built all we enjoy today, instead of wallowing in perpetual skirmishes and wars like we see in all the history books. Disempowering “the people” in terms of gun ownership is more empowering in others than you’re appreciating. There’s a lot of stupidity out there, and for the sake of making yourself more dangerous at the cost of making them more dangerous too, you become just another one of them.
If everyone was as dangerous as the police, the police would be useless. Without a monopoly on violence, you get unregulated vigilantes like everyone seems to idolise if their popular portrayal in the entertainment industry is anything to go by, and you get organised groups of protection racketeers, who you can choose to pay instead of being forced to pay through tax. Only thing is, if you don’t pay, you get murdered, and the sharp good vs. evil distinction you get in the entertainment industry is nothing like real life where everybody believes they are the good guy. We’ve seen the wild west, we’ve seen the mafia, we know where it goes and how it ends. Were they really more free? Only in a sense were they more free, but the net freedom was lower. Being free to be violent such that you are extremely likely to get murdered is not freedom - some freedoms need to be curtailed in order to optimise overall freedom. It’s a case of figuring out what needs to be controlled so that the most possible other things don’t need to be. Guns are one of the things that need to be controlled in order to attain maximum overall freedom.