The Grizzlies may be a better fit than the San Antonio Spurs
An area of the game that the Spurs are currently lacking in that DeRozan would greatly benefit from is three-point shooting. The Spurs' leading three-point shooters this season were Rudy Gay, Patty Mills, and Lonnie Walker IV, shooting 38%, 37%, and 35% from beyond the arc respectively.
While DeRozan is still able to score well because of his ability to create his own shot and draw contact, he would benefit from having better floor spacing and having better three-point shooters to kick the ball to. This past regular season, Desmond Bane, De'Anthony Melton, and Grayson Allen were able to shoot 43%, 41%, and 39% from three respectively on four or more attempts per game each.
The Grizzlies have managed to build a very good young core of players that compliment each other well. Because they are already on the cusp of making a playoff run, having a veteran on the team that is capable of scoring in the clutch and making plays for others would be invaluable for such a young team.
If that isn't enough, DeRozan also already has experience playing with Jonas Valanciunas from their days with the Toronto Raptors, which would likely only add to the chemistry DeRozan would have with the team. In my mind, the Grizzlies are an overlooked landing spot for DeRozan and could be the best place for him in terms of fit with the team.
At this point, while the Grizzlies do not have as much cap space as the other two teams on this list, they should be able to clear some room relatively easily. The primary concern would be to not give up too many of their best three-point shooters in the process.