Windfall got restricted with a slew of other cards during Urzas Block (Saga, Legacy, Destiny) because of Tolarian Academy. People played with a deck with full Power 9 plus 4 Mana Crypt, 4 Mana Vault, 4 Lotus Petal, and 4 Academy. This allowed them to almost consistently have enough mana to cast Windfall, Time Spiral (both also 4 ofs) or Twister or Jar turn 1 every game, constantly drawing 7 cards and producing more and more mana. Turn 1 drop a million mana, cast Windfall, draw 7 was way too easy and common. Today not only are people playing way cheaper decks, but are also playing loot cards to make hands smaller (dack), cards that stop draw (notion theif, spirit), cards that make it cost more (Thalia, Spheres, Thorns etc), and new counters (flusterstorm, mindbreak trap) that all make this card weaker or completelt null (topdeck wars, or versus Dredge which did not exist at the time, Dredge alone makes this card horrible, or "ok" if dredge ran it itself and managed to get 3 mana to cast it, but considering most dredge lists dont use Wheel or the one copy of Windfall allowed them I dont know if this would change anything as a 4 of etc). Without the full mana rocks and 4 of Academy, Windfall has not been what it was for years, a 3 mana draw 7, and anything past turn one or 2 is prolly no better than a sorcery speed draw 3-4 at best. This makes it "worse" than Gifts, FoF, and Thirst which all have been unrestricted. Honestly Windfall should of been unrestricted when Time Spiral and Stroke of Genious got unrestricted. Hope that clears that up as to why it got Axed, and why it should not be now.