Peter Pan’s Flight in
DISNEYLAND is a different ride system and the ride vehicle is stopped for each guest.
The
official answer for WDW for both Peter Pan and Peoplemover is and that stopping is done only in the rarest situations - the term I was given is ”almost never”. This includes when they may allow a guest(s) with disabilities to ride Peter Pan either as first riders or last riders of the day (which Michigan’s daughter have done).
Officially, for Peter Pan, even slowing the belts at both is done only in “extremely unique” situations. The biggest reason at Peter Pan is the fact that the belt is designed to move at the same speed as the ride vehicles so slowing (or stopping) the belt also slows (or stops) the ride vehicles within the attraction where people are suspended above the ground.
WDW has had multiple situations where people either attempted or did get out of ride vehicles (ones I recall offhand include Peoplemover, Spaceship Earth, Splash Mountain). Those attractions have walkways and stairs to get riders out if an evacuation is needed. Peter Pan doesn’t.
Does this mean those 2 are never stopped - no - but it’s extremely rare (to the point of it should almost never happen).