How does the "legendary rule doesn't apply" mechanic impact gameplay in Magic: The Gathering?

The "legendary rule doesn't apply" mechanic in Magic: The Gathering allows players to have multiple copies of the same legendary card on the battlefield. This can impact gameplay by enabling players to use powerful legendary cards more freely without being restricted by the usual rule that only allows one copy of a legendary card to be on the battlefield at a time. This can lead to more strategic and diverse deck-building options, as players can include multiple copies of their favorite legendary cards in their decks without worrying about the usual limitations.