This scenario was brought up as an option by Mike Luciano, who covers the Raptors for Raptors Rapture. San Antonio would send Jakob Poeltl and Thaddeus Young to Toronto in exchange for Goran Dragic and Chris Boucher, along with their 2023 first-round pick.
The Spurs would acquire a long and versatile big in Boucher. Most Spurs fans probably remember the play from a couple of years ago in Toronto when DeMar DeRozan finished a posterizing dunk over Boucher for the and-1, but he's a very skilled shot-blocker and athlete despite his smaller frame.
As for Dragic, he would likely be later diverted in exchange for another player or pick. With the Spurs' current depth at the guard position, he wouldn't be much of a fit on their roster. And if Dragic did end up being traded by San Antonio, it wouldn't be the first time, as they previously traded him back on draft night in 2008.
This would be a very solid outcome for the Spurs, as it would give them even more depth at power forward/center, and get them another asset that can be flipped in further moves as we approach the trade deadline. The extra first round pick is the icing on the cake.
But maybe trade scenario two might be more tempting?