The Antetokounmpo talk is insane, Conley to the Jazz was not unexpected, many of the others ended up sign and trades but their leaving their then in bent teams was not unexpected and the Spurs don't have the assets to trade for a superstar or star.
You always need a young or youngish centerpiece to pull that off and right now they lack that. White is the closest, but he's also already 26 and seems destined to top out in that nebulous zone between star and role player, a la Brogdon or Van Vleet.
White is in their class or capable, but because he's not as established, the Spurs are going to get luck and get him for probably 4/$60-70M, $15-25M less than they received.