So Avengers: Endgame kicking off its second act with a failed gambit at defeating Thanos would be a good idea for the plot, as it would prove once and for all that those powered gems of the universe are necessary for victory.
On the one hand, chasing Thanos to get the stones is wise, as the clip proves they have a good idea of where to find him post-Decimation.
However, there’s also a good chance that the battle could come after the Infinity Stone heist that Black Widow is suggesting kicks off.
(Or post Snap, if you’re still not behind that official name’s usage.)