So she was an L6 manager, maybe a lower-end L7 manager, but my guess is still L6. That's not even anywhere close to "exec" level. It's the entry-level management position at Amazon.
The sexism claims sounds brutal, but it grinds my gears when some news outlet tries to make it sound like some middle-manager grunt was "an executive". And if you take away the "Ex-Amazon exec" claim, this story really just becomes "yet another ex-Amazon person that was put on a performance improvement plan and feels wronged by it", which is understandable and maybe there's a valid case here for retaliation... but it's not newsworthy, and certainly doesn't fit the title.
edit: just read the complaint, she reported to an an L6, which means 99.9% she was an L6.