They can't learn this because this ideology is populism, and a lot (most?) educated people are against this type of campaigning.
However, we must admit it is effective and it would do the democrats good to be more populist. It's just hard to be populist without resorting to emotional appeals, propaganda, fear mongering, misinformation, etc.
That's not what I'm saying. Populism represents an ideology about policy, i.e. do what the people want. My argument that "Politics is show business" is about the presentation of a campaign, not its content. One can use a persuasive presentation to market any policy viewpoint, populist or not.
Trump's campaign has alternately incoherent and destructive policy proposals, but the narrative he presents is exquisite (without being necessarily true): "A popular and successful businessman selflessly sacrifices his own comfortable lifestyle to bring common sense to politics by sweeping away greedy bureaucrats and wasteful institutions, along the way surviving assassination attempts, criminal charges, and a malign media campaign to discredit him." It's a great story, with heroes and villains. It's easy to get swept up in that story and want to be part of it. Certainly Trump's experience as a TV star has given him insights into crafting a narrative that engages with people.
The Democrats' have sensible policy but virtually no narrative. At best (as someone tweeted, can't find original source now) the Democrats are in the position of defending imperfect institutions. The Dems blow loads of money on ad buys, but what they need is writers to create a story that engages people emotionally.
However, we must admit it is effective and it would do the democrats good to be more populist. It's just hard to be populist without resorting to emotional appeals, propaganda, fear mongering, misinformation, etc.