You do understand that there are black people who do support and have voted for Donald Trump, right? And who are you to judge that her act was not sincerely for the sake of unity rather than profit? If it was the other way around (if she sang at Biden's inaugural) and she said it was for the same reasons, you wouldn't hold scrutiny towards her as you do now, would you?
In the end--no, it is not a big enough deal to the extent of the BS in which Michele had to endure. A firing squad aimed at her career is uncalled for and is just another attribute to the horrid self-righteous movement that is "cancel culture".