The role is not working in the array of data, like in an example from google charts docs: https://developers.google.com/chart/interactive/docs/gallery/barchart#labeling-bars

Example:

[ ['Element', 'Density', { role: 'annotation' } ], ['Copper', 8.94, 'Cu' ], ['Silver', 10.49, 'Ag' ], ['Gold', 19.30, 'Au' ], ['Platinum', 21.45, 'Pt' ] ] 

P.S. Not only the annotation role doesn't work - no one works