Why IND do it:
Add a very needed multipositional defender to their team
They can upgrade a key position without giving a key young guy in a Siakam trade
Instead of having to pay Toppin, they use him as a trade bait now that he's gained some value with his good play
Grant's contract is not a huge problem for Indiana since they only have Hali on their books longterm
Why POR do it:
Hield would be flipped to another team for some seconds
Toppin is a friendly offensive player to their young core
Smith adds them one more quality big with Timelord out and Ayton fighting injuries