Upon further investigation, this is somewhat my fault for not understanding how the feature worked.
I was still trying to tap the right side of the screen to advance to the next panel, however, when the reading direction is flipped, it’s expecting you to also tap the left side.
It would be nice as a general setting for all readers to have a separated “advance to next page / panel side” gesture / tap.
Since I hold my phone with my right hand, I want to tap the right side to turn to the next page / panel, even if the reading direction is reversed.