>>43682020>>43682020Honestly can't say much about Ho-oh but I think the reason why Mewtwo stays so memorable is because of what Takeshi Shudo's writing did for the character in the anime. Without Shudo, Mewtwo would have stayed as some generic "secret boss" character as it was Shudo who took its status as a cloned-Pokemon to a deep philosophical level.
To answer your question as to why they haven't had any good lore OP, its probably because the franchise has not found another writer like Shudo, and it has done so on purpose. Shudo was pretty controversial as a screenwriter because he didn't always want to write stories that were just for kids.
Now we just have dumbed down, formulaic scripts and storytelling in the anime and games because TPC arbors anything that borders on mature themes. Because shit stories sell apparently.