The Battlemages were simpler, as they were "virtual vanillas," meaning they had effects when you played them but were just 2/2 creatures for the remaining turns, so they went into Planeshift
Despite being not particularly hard to pull, Gold Stars have a couple fundamental advantages
Liliana's Standard Bearer, Midnight Reaper, Knights of the Black Rose, Locthwain Lancer, Elenda and Azor, Pull from Tomorrow, Painful Truths, Read the Bones, Distant Melody, Path of the Enigma, Conjurer's Mantle, Vanquisher's Banner, Chivalric Alliance 13 card draw
Deathrite Shaman is great when the game goes long, but if a Modern game goes long, it's usually because Teferi, Hero of Dominaria or Jace, the Mind Sculptor is drawing tons of cards, or Elementals are playing through their deck, play patterns that Deathrite Shaman can't keep up with