It would have been possible to preserve the actual tragedy of the old lore though. If you look at the comic for the new lore, Varus went into the pit not knowing what it was. In the old lore he knew it was a dark force already.
When he chose to accept it and let it corrupt him it was so much more tragic and meaningful in the old lore because he knew exactly what he was doing and he did it anyways.
In the new lore he basically just ran to the pit in his grief, and fell for its trap instead of knowingly choosing to accept the evil within. Riot could have kept the knowing acceptance of it and still had their update mostly the same.