that's because lore is not THAT relevant :x sadly, You cannot make a game out of lore, at least not a moba since a reading/writing game would require constant story development which doesn't happen in a moba, in LoL characters are static and are not meant to develop in other ways but in gameplay. Riot invest a crazy amount of resources trying to overcome this hurdle, yet everyone hates the narrative team... shame on you.
Also, if the format players interact with lore is "wall of text" than it becomes less relevant because most people just overlook walls of text. That's why Riot is trying to do short lore where the main idea behind a champion is exposed and eventually people become curious about it THEN, when they're eager and hooked up, you give them the long wall of text, plus some fun interactions in-game.