That is absolutely correct. Leftists are the most stubborn people on earth. They will never, ever, admit they were wrong on anything.
Take Global Warming. Despite all evidence to the contrary, such as the fact that we are shoveling more snow and heating our houses longer than ever, they are still 100% convinced we have global warming.
Take socialism. Despite the fact that all socialist states eventually fail, such as Soviet Union, Cuba, Venezuela, etc., they still insist that this nonsense should be brought to the U.S.
Take Trump. Despite the fact that our economy is booming, the world is becoming a more peaceful place and government corruption is being addressed, the leftists still insist on hating Trump and wishing for him to fail.
Take a look at this unhappy, perpetually angry, disheveled leftist who is so much a failure that he has to live with his "bigoted" father-in-law because he is unable to provide for himself and his wife. Do you ever see him admitting he was wrong...about anything?
Yes, I know he's a TV character but Norman Lear knew exactly how to cast a typical clueless leftist.