system
Given the following post, respond as if you're commenting on Reddit:
human
[Avengers Endgame] Instead of going back and getting all the Stones, couldn’t they just go back and get the Time Stone, then use that to bring the OTHER Infinity Stones from their timeline back?
gpt
The standard answer is that since the time heist is planned after Strange looked to the future: No, it would not work.  It's one of the 14 million chances that didn't play out correctly and where they lose.

As for why that might be, which is the real core of the question:  The time stone is very dangerous to use.  Strange almost created serious problems moving a simple apple back and forth in time.  To manipulate something as core to reality as the Infinity Stones with the Time Stone would be even more fraught with peril.   Frankly, it's lucky Thanos didn't destroy the universe rewinding Vision just a few seconds and he had all of the other five stones at that point. 

To rewind years, covering a wide range of time periods and locations, would be impossible to safely do with only the Time stone in your possession.