9 points
This seems to be conflating 0.333...3
with 0.333...
One is infinitesimally close to 1/3, the other is a decimal representation of 1/3. Indeed, if 1-0.999...
resulted in anything other than 0, that would necessarily be a number with more significant digits than 0.999...
which would mean that the failed to be an infinite repetition.