White's Current State in MTG

[Aetherium Slinky]

Your scenario obviously requires some setup and green is best equipped to take advantage of an empty board. I think white would be playing into green's pocket with an Armageddon in a generic situation. Even with Crucible of the Worlds. Selesnya on the other hand...

[WizardSpartan]

I mean, green is probably the color most affected by land destruction (unless it uses a lot of mana dorks). Non-green decks rely on artifacts to ramp them, and may have access to a couple mana after the wipe. It's likely that a green deck will only have mana in the form of lands, so when Armageddon comes down, they lose everything. Can't cast Cultivate if you have no mana. Only exception would be the obvious effects of Crucible of Worlds/Ramunap Excavator, but in that situation, the white player just wouldn't Armageddon.

Still, it depends on the boardstate, but assuming an even state, a white deck that has built their deck to have access to effects like Sun Titan will most likely be the best at taking advantage of it.

[ImaSaber]

If you look at white, there are some actually formidable cards. Who doesn't think when Land Tax, Smothering Tithe, or Stoneforge Mystic enter the battlefield. White pioneered wraths with Wrath of God. But white's obvious downsides keep lots of players from using it purely because there are so many more better clors in Magic, no matter which format you play.

White does have some staple cards in many formats, but it just seems like while white has a few viable options, other colors have a plethora of great cards. Another point I would like to bring up is that typical white effects are being taken by other colors and on better cards. The newest example I can think of is Aven Mindcensor, and a new card from Commander Legends called Opposition Agent. Opposition Agent (OA) is strictly better in every possible way than Aven Mindcensor (AMC). OA has better power toughness than AMC, it stops people completely from searching libraries, where AMC still lets you search the top 4, OA lets YOU tutor their deck for a card AND play it with no downside. In theory you can take the best card in their deck, exile it and not play it so it can not hit their graveyard, essentially taking care of a threat you didn't even know about. Stopping tutors has been a white effect mostly, as seen on Leonin Arbiter, and now these cards seem completely irrelevant because OA does everything better with no downsides. Vigilance also used to be a mostly white ability but now is stapled to cards like Questing Beast, and Elder Gargaroth. The point I'm trying to make is that anything white can do, other colors can do more effectively, or just as effectively, which has lead to the lack of white in most formats.

[Slyvester12]

I think you're neglecting white's real identity: life gain and pillowfort. White can gain life and prevent attackers better than any other color. Other colors have cards that can play into this, but they don't have the pure life gaining power white does.

Those are definitely not desirable abilities for a lot of decks, though. It's not so much that white lacks identity. It's more that white's identity sucks.

[ImaSaber]

I think you're neglecting white's real identity: life gain and pillowfort. White can gain life and prevent attackers better than any other color. Other colors have cards that can play into this, but they don't have the pure life gaining power white does.

Those are definitely not desirable abilities for a lot of decks, though. It's not so much that white lacks identity. It's more that white's identity sucks.

I think the reason that white's identity is not so great is because it lacks payoffs, or the payoffs are to difficult to get to. Lots of the rogues from Zendikar Rising have an ability or buff that occurs when the opponent has 7 or more cards in their graveyard. This is not a hard feat to achieve when most of the cards played in the deck mill the opponent. Cards like Serra Ascendant have a condition that is possible, but hard to get to consistently. I think this is why the lifegain part of white does not really see play unless it is stapled to a multicolored card like Dream Trawler.