Before we get into why each team would make this move, it helps to see the entire framework at a glance.
San Antonio Receives: Giannis Antetokounmpo
Milwaukee Receives: Devin Vassell, Keldon Johnson, Stephon Castle, a 2027 first-round pick (via Atlanta), a 2029 first-round pick, a 2031 first-round pick (swap rights with Sacramento), a 2032 first-round pick swap and three second-round picks
Feel free to quibble over the number of picks involved. San Antonio has more seconds to give. Including Carter Bryant could eventually be in play, too. Swapping Harper in for Castle may reduce the number of outgoing firsts.
There are multiple ways to potentially get there, but this one checks boxes for both teams.
