This is the first time I've heard of an event designed to be harder for older players. Logically it appears that players are punished for playing the game a lot. Personally, as a completionist, by being blocked from completing this event I no longer find the game worth my time.
Another matter that should be addressed is the ridiculous healing rates of AI, especially in the tower, where 3-5 thousand HP restored in a single move is common while players are healed for much less. There's no challenge in the fights themselves, they just take forever to finish, which for a 'match 3' game isn't really that great.