These arguments are based on the axiom that people are a bunch of ignoramuses to whom any idea can be sold.

Lol. What does "ignoramus" have to do with it? Do you really think you're so special that nothing can be imposed on you or used to control you? The secret is that you are already being used, whether you like it or not. The most impressionable, active, and patriotic people, those with some kind of personal interest, are already at the Maidan; these are the ones who are fighting for the idea. Let's put them in the first category.

The second category, also impressionable but negative, consists of people who have an exclusively "personal opinion" about what is happening, along with their inflated ego, which allows them to think this way. They have "their own opinion" on everything, endlessly arguing on the internet, with colleagues at work, at home (if there are any who disagree). These are armchair analysts and expert debaters. Some of the most daring of them sometimes end up in the first category ^^.

The third category. According to your words, these are "people with more than one brain cell, who begin to protect themselves from intrusive propaganda."
But, on the contrary, they don't protect themselves from information; they try to figure out what's going on and where the wind is blowing. Who benefits from this? Why? And so on. They don't shout on forums, they don't agitate; instead, they analyze this information and what is happening.

The fourth category. These are the people who don't care. Maybe not entirely, but as long as "my house is on the edge and it doesn't affect me," then it doesn't affect me.

I can say that there are very few people in the fifth category, those to whom it is completely irrelevant. Really, not just for show.

We won't consider bots and trolls. Of course, this is just a rough estimate, as many mixed subspecies can be identified.

This is fundamentally wrong; humans differ from animals by their intelligence.

Of course, there is intelligence, psyche, perception of information, and its processing.
And since you don't live in a cave, you receive information of various kinds. Both "for" and "against" the Maidan. Roughly speaking, in a microcosm, this is live communication, when you hear the opinions of friends, acquaintances, and family, and in a macrocosm, this is the media. And will you deny that this has absolutely no influence on you? And that it doesn't shape your opinion? Or should you not be so naive, dishonest with yourself, or blind?

You say that people are dissatisfied with this and that, and that it has been brewing for years, and that's true. We don't live in a great world. All that needs to be done is to stir up the people. Which has already been done. And now it's gone too far; "beat the Jews, save Russia," "spontaneously," as it happens.