There are a lot of people who are "tired of white people always being called racists with no evidence" who feel Trump gets a bum rap who would go "oh yeah, he said the n-word, he's racist" and move on from him. Not to mention the ones who want to defend him but don't want to be seen as racist themselves. This would remove their last bit of shield to hide behind.
He bragged about finally not violating the Civil Rights Act of 1964 in the 90s when he opened his ritzy club in Miami in the last debate. Those "tired of white people always being called racists with no evidence" will hang onto to that in face of evidence as his attack on Judge Curiel was textbook racism.