It's a real thing.
google white savior in literature/film
lol, I'm perfectly aware what white savior complex is, believe me. The exception I'm taking is I don't think the author of that column is saying TKAM is an example of white savior complex, it's set in 1930s Alabama, there wasn't an abundance of black public defenders. I believe she's saying how the book is taught and presented in 2022 feeds into a white savior complex .
The Woke's don't like To Kill a Mocking Bird because it's about white people being saviors or something.
This is not the point of the column you posted. I think she's saying that if you're going to use that book to teach you need to dig deeper than Harper Lee did, she wrote that book 60 years ago, times have changed and what we teach needs to change to reflect the times.