I wonder about this. There are many reasons I can see:
1- Elitism. The left hate the working poor, and despise their values. They believe themselves to be superior, and are appalled that someone who speaks to the working class in common language is president.
2- Brainwashing. They want to believe that the presidency of the USA is some exalted position deserving of flowery language rather than the crude language Trump uses. They have lost sight of the fact that the president, like all federal employees, are
civil servants who should be there to serve the people rather than rule over them..
3- More brainwashing. They believe that Trump is a Nazi, white supremacist, etc., because they are told it daily by their preferred media sources, who know that people rarely check facts for themselves (especially when they are being told what they want to hear.)
4- Mental illness. A significant part of the US populace is suffering from various forms of mental illness - and many of them are taking drugs that make things worse. I think the perversion or loss of societal and moral values has left people astray, alienated and frustrated with life. Formerly solidly accepted values are now all wobbly. What's celebrated by the media is essentially fame, sex and money.
When people are unhappy or frustrated, it's easier to strike out at things they can't control (politics, tragedies in distant countries) than to deal with their own very real problems. In fact, I am probably doing that myself right now! So.. back to work for me....
