In "Blues Ain't No Mockin' Bird," what is author Toni Cade Bambara's tone?

The term tone is defined as the author's attitude toward the subject or the audience. Tone is expressed through the writer's word choices, which helps capture the way in which the writer is addressing the central theme in the work ("Tone," Literary Devices). Tone contrasts with mood in that mood is the atmosphere of the work, the emotions the writer evokes within the reader. While the mood in Toni Cade Bambara's short story "Blues Ain't No Mockin' Bird" is fairly comical, the story deals with very serious subject matter, and Bambara deals with that subject matter through a very serious, indignant tone, the serious subject matter being racial discrimination and treatment of the poor and suffering.To feel indignant is to feel a strong sense of disapproval about "something considered unjust, offensive, insulting or base" (Random House Dictionary). Bambara particularly reveals her tone in Granny's speech about the treatment of the man about to jump off the bridge. After Granny tells the men to leave her property because she feels it is wrong of them to film her poverty, she turns to the children under her care and relays a story from her past about a man about to commit suicide. Everyone surrounding the man, including his wife, the minister, and the townspeople, showed genuine distress and begged him not to jump. Yet, a person with a camera decided to start photographing what many would think of as a newsworthy scene. Granny understood that, in filming the scene rather than doing anything to help, the person was doing nothing more than exploiting the suffering of the man who wanted to commit suicide. Granny expresses her righteous indignation at such exploitative behavior in her following speech:

So here comes ... this person ... with a camera, takin pictures of the man and the minister and the woman. Takin pictures of the man in his misery about to jump, cause life so bad and people been messin with him so bad. This person takin up the whole roll of film practically.

Bambara's own indignant tone echoes in the indignation Granny expresses in her speech. The phrases "man in his misery" and "messin with him" not only capture the sorrow of the scene but the author's sense of right and wrong. The author is conveying that it was because the man was made to suffer, most likely out of racial discrimination, that the man had been driven to want to jump. Taking photographs of such suffering, rather than doing anything to help, only glorifies the behaviors that had driven him to jump in the first place. In expressing her view of right and wrong, Bambara is also expressing her serious, indignant tone.
https://literarydevices.net/tone/