I'd recommend the New Yorker article:

https://www.newyorker.com/magazine/2020/02/17/was-jeanne-cal...

Despite all the good reasoning about it being impossible to live that long, what does it for me is that people in her town, where she was well known, would have had to have not noticed Jeanne die and her daughter take her place. Including her doctor.

Not saying she definitely isn't a fraud, but the evidence against her is more hypothetical and the evidence for her is more solid.