Mono-White Aggro floods the board with small creatures like Novice Inspector, Thraben Inspector, and Lunarch Veteran, most at 1-2 toughness, making Drown in Sorrow's -2/-2 sweep extremely effective. Arms of Hadar similarly wipes their token/small-creature board for -2/-2, a strong rate against their wide aggressive starts. Suffocating Fumes only provides -1/-1, insufficient against their 2-toughness creatures, so it's cut in favor of the harder sweeper. Extract a Confession is single-target and symmetric risk against a token-heavy opponent (they choose the worst creature to sacrifice), so it comes out for more impactful sweeper effects.