I actually believe that people accept the deaths and the diasasters because to acknowledge that Johnson is what he is- a liar, a fool, a manipulator, a grossly irresponsible and incompetent moron - is to acknowledge that they were duped into voting for Brexit.
He was and is Brexit. As the article says,it could never have happened without him and his support. His wry smiles and chuckles reassured people who didn’t understand Brexit that it would actually be ok. So to turn on him now and recognise the charlatan and con artist that he is is to admit that you got fooled and correspondingly to admit your own stupidity in the referendum and after.
Human nature will not allow that. So he gets a free pass for anything he does and the country crumbles around his erect Union Jack.