Republicans have had a dirty politics strategy for 25 years or more.
At How Newt Gingrich Destroyed American Politics - The Atlantic McKay Coppins says of Newt Gingrich,
"I think that his defining legacy is he enshrined this combative, tribal, angry attitude in politics that would infect our national discourse in Washington and Congress for decades to come."

"Few figures in modern history have done more than Gingrich to lay the groundwork for Trump's rise. During his two decades in Congress, he pioneered a style of partisan combat--replete with name-calling, conspiracy theories, and strategic obstructionism--that poisoned America's political culture and plunged Washington into permanent dysfunction."

In the 1994 midterms his "Contract with America" 10 bills Republicans promised to pass if they took control of the House. 300 candidates signed it.
As Election Day approached, they maneuvered to block every piece of legislation they could--even those that might ordinarily have received bipartisan support, like a lobbying-reform bill--on the theory that voters would blame Democrats for the paralysis. It worked voters frustrated with Congress voted for change and the republicans picked up 54 seats in the house.

People in Rural areas who have been left behind by the information economy need a community to fight back.
In Opinion | The Rotting of the Republican Mind - The New York Times (2020), Davis Brooks says.
"Over the past decades the information age has created a lot more people who make their living working with ideas, who are professional members of this epistemic [the philosophy of knowledge. It seeks to answer the questions "What is knowledge?" and "How is knowledge acquired?] The information economy has increasingly rewarded them with money and status. It has increasingly concentrated them in ever more prosperous metro areas.

Meanwhile people in rural areas have flatter incomes, decimated families, dissolved communities.
People in this precarious state are going to demand stories that will both explain their distrust back to them and also enclose them within a safe community of believers. The evangelists of distrust, from Donald Trump to Alex Jones [An American far-right radio show host and conspiracy theorist] rose up to give them those stories and provide that community.

"Under Trump, the Republican identity is defined not by a set of policy beliefs but by a paranoid mind-set. He and his media allies simply ignore the rules of the epistemic regime and have set up a rival trolling regime. "

"The only solution is to reduce the distrust and anxiety that is the seedbed of this thinking. That can only be done first by contact, reducing the social chasm between the members of the epistemic regime and those who feel so alienated from it. And second, it can be done by policy, by making life more secure for those without a college degree."

Trump is taking the strategy of disinformation that has worked in the past to a whole new level.
In a 2018 essay The Constitution of Knowledge in National Affairs, by Jonathan Rauch
He starts out with a recap of a 2004 television interview Trump did with Chris Matthews on MSNBC, Trump marveled at the Republicans' successful attacks on the wartime heroism of Senator John Kerry, the Democrats' presidential candidate. "[I]t's almost coming out that [George W.] Bush is a war hero and Kerry isn't," Trump said, admiringly. "I think that could be the greatest spin I've ever seen." Matthews then asked about Vice President Dick Cheney's insinuations that Kerry's election would lead to a devastating attack on the United States. "Well," replied Trump, "it's a terrible statement unless he gets away with it." With that extraordinary declaration, Trump showed himself to be an attentive student of disinformation and its operative principle: Reality is what you can get away with.
Trump understood the basic concept of disinformation.
The fact is that President Trump lies not only prolifically and shamelessly, but in a different way than previous presidents and national politicians. They may spin the truth, bend it, or break it, but they pay homage to it.
Trump got his press secretary to lie about the crowd size at his inauguration seeking to put the press and public on notice that he intends to bully his staff, bully the media, and bully the truth.
The Man Who Broke Politics - How Newt Gingrich Destroyed American Politics - The Atlantic McKay Coppins
Terry Gross interview of Coppins.
Opinion | The Rotting of the Republican Mind - The New York Times, Davis Brooks, Nov 2020
The Constitution of Knowledge | National Affairs, Jonathan Rauch