Given the attention to stuff like pick swaps six years out as well as other future assets, it feels like the media, bloggers and fans tend to miss how dynamic the league is with roster turnover. A lot of stars stay put but a lot move around too. If you are a veteran player with above average skills and a reasonable contract, short-term leases in your city of employ seems like a smart strategy.
Again, simply look at the teams over from the '19-20 season to now.
Four of the top twenty scorers by PPG (Harden, Westbrook, McCollum and DeRozan) have moved on to new teams and some have moved twice (Westbrook). If I wanted to get technical, I could argue that the number is actually five because Wiggins was traded near the deadline that season.