[SpEEdyBL]

To answer the original question; why people think going going up to 6s from 4s without changing anything else, is simple.

They are probably the same people who have no idea what 6s on the same motor would be like and end up driving very cautiously if they don't already break parts before something overheats. This perpetuates the assumption that moving up in voltage alone reduces current, as they go on and brag to their friends about their experience.