Luka Dealt to Lakers: Nico Harrison is a Basketball Terrorist

[F Gump]

Especially if Luka gets a couple of rings with LA.

Yep, "and then what happened" will have a considerable impact on the future narrative.

But that is going to be true from both directions. 

As you mention, if Luka wins a couple rings with LA, that validates the "Mavs messed up badly" narrative. The "bad trade" examples being offered - Herschel Walker trade, and Babe Ruth trade -- resonate because one side in the trade ended up being a MAJOR winner of multiple titles while the other was left in the dust.

But if Luka doesn't win any titles after all, then the narrative might shift considerably, even if Luka continues to bring entertainment value. And it all would look the exact opposite from what we think now, if the Mavs are the ones who somehow end up winning titles instead of Luka.

IOW it's not just what happens to Luka re titles in the next 3-4 years, but also what happens to the Mavs, that will shape the narrative that lasts.