My guess (only a guess) is that the revised scoring system messed with her head. She was singled out as being too good, and the judges has to depress her scores to benefit other, less spectacular athletes.
I think she walked away from the corruption of the institution.
I probably would have done the same.
That is absolute rubbish. If she's been singled out for low points, how come she won 4 golds in Rio in 2016?