If you zoom in there are also artifacts in the text. The legend is text that has all been resized differently, which you would not have to do in any normal graph software. The light grey bar is not square and has an odd shading pattern, it's like an inside gradient but not consistent enough. The corners are rounded but not consistently. The text has smeary artifacts, gaps, and is not consistently filled in. So yeah, likely an ai image.

Weird because you can quite easily get AI to use a graph program.