Deaths Shadow, Liliana of the Veil, Blood Moon, Leyline of the Void, and Omnath, Locus of Creation all get cleanly answered by Purge, so I expect this to be a mainstay in the sideboards of White decks regardless of what the metagame looks like
You dont need to be an 11+ swamp deck to take advantage of this
You can easily blast away someones creatures early on with removal (that person would have a limited defense) and stab him or her a few times with this
On top of this it is converted mana cost you need to match rather than toughness which for creatures is typically lower
A breakdown of the archetypes in the Vintage metagame, according to MTGGoldfish, looks something like this: The problem with understanding Vintage is that with such a high concentration of powerful cards in the format, even with an archetype breakdown in front of you, it can still be mystifying to the uninitiated