No one thinks Hillary's "basket of deplorables" line was a good idea. ...Literally no one. Even her closest allies and aides can see that it was a huge mistake. For a candidate who already had immense difficulty generating any excitement, it was a message to necessary voters that she didn't want them on board. They were, after all, "irredeemable" people and she was taking a moral stand against them.
Unfortunately, they represented roughly half the country.