>>46228336I only really remember most of the ones from early games because of the anime and manga. From a purely game point of view later leaders that do shit outside of their gym are more memorable then many of the gen 1-3 leaders. Like I remember 4 leaders for their outside interactions (Crasher Wake and Barry's interactions, Maylene being on her way to see Candice, Roark doing the Underground tutorial, Flint and Volkner's friendship, etc), and 5 leaders because many of them participate in the story on a bigger scale. I also remember the gen 7 trail captains because you spend a bit of time with them compared to past leaders, and you can learn about their home life and meet NPCs related to them. Even gen 8, as shitty as it is, I can remember the cast pretty well because the leaders are reused at various points in the post-game/dlc as recurring characters. I think this is why so many people can't remember the gen 6 leaders. They're sandwiched between a bunch of games that made an effort to incorporate the leaders more into the narrative but outside of Korrina they don't do anything.
That's not to say that's true of every gym leader or E4 member from those games. Like Watson is pretty memorable, Giovanni, and gen 2 female leaders. They have more explicit roles in their games that make them somewhat memorable but the rest of them were just designs for other media to flesh out. I mean really when people think of Lt. Surge do they actually ever think about his game counterpart first? Because my mind always goes back to the anime and manga version. Same with Erika, or Blaine. This is kind of true for gen 1 in general though. People regularly believe that Mewtwo is part of the Team Rocket stuff because every other media ties them together even though the first game makes it clear that the two are separate plotpoints.