Part of the problem is that people are all too ready to tolerate, accept, even approve of lies as long as they like the lie or the liar. That is why a still-substantial minority think Johnson is ace when anyone with half a brain can see he's an incompetent, selfish, lazy, con-artist who would sell his own granny if he could get a price.
The second problem is that a lot of people think they know far more than they actually do. The Dunning–Kruger effect. This is why every cnut you meet is an expert on macroeconomics, foreign trade arrangements, local government finance, medical science, education, who Pep should play on Saturday - you name it. It is tending to make the country literally ungovernable, and unscrupulous politicians are making use of this for their own nefarious ends.