Dream Team has the best credits theme, through and through. It takes every major theme in the game, remixes them, and combines them into a credits theme unmatched by any other. If only it included Dream's Deep...
Odyssey is a good honorable mention. Like Dream Team, it combines the major themes of the game, although it doesn't remix the themes like Dream Team does. Jump Up, Super Star is absent, but at least it uses the version of Fossil Falls used in the reveal trailer.
Paper Jam had a good credits theme as well, but like Mario Odyssey, it combined the themes but didn't rearrange them. It's just a bit lower than Mario Odyssey on my list, though.
EDIT: Hearing Paper Jam's credits theme again, I see that it actually did rearrange the major themes of the game. But I still give Dream Team the edge due to that game having an all-around amazing soundtrack compared to Paper Jam.