I doubt she did it herself. It is plagiarism—and plagiarism doesn’t necessarily reach a point of legal damages and recourse.
Of course the Clintons are criminals who shouldn’t be on the streets let alone near public office—and Melania isn’t.
Yes, this unfortunately plays into the hands of the biased media. And, on top of that the media are too often unfairly quoting Melania as having said she wrote the speech herself, without adding the qualifier that she had volunteered at least where I saw her saying that, which was “with as little help as possible”. That essentially was saying that she, like any political wife speaking on such a stage, had speechwriters involved.
Again, the speechwriter responsible for it is to blame, and the motive of that speechwriter should be examined carefully, as it well could have been a case of Never Trump sabotage.
Media is also reporting that Melania’s bio in the program indicates she graduated from college when in reality she dropped out after one year.