Donald Trump is an evil genius. His debate behavior was his latest deception. He acted like a somewhat normal person. He was out of character. He did what he needed to do — he didn’t behave like the person he is. One more con job.
Most people know who he is and how he “normally” behaves, as he is constantly putting himself in the limelight of the 24/7 news coverage. There is no way to hide from him.
So his relative transformation in the last debate is much too little and much too late to fool anyone.
Of course, his true believers continue to follow him no matter what he says or does [more].