I decided to look up the road wRC+ of Rockies hitters. Wasn't sure how far back to go, so I used 2002, the year they installed the humidor at Coors Field.
Here's the link to the Fangraphs report:
Rockies hitters, 2002-2021, road stats only
Among the most experienced Rockies, Story is about 20% (per road wRC+) behind Helton, Hawpe, and Tulowitzki. He's also behind Arenado and Holliday, but only about 10%.
He's close to Seth Smith, Blackmon, and Carlos Gonzalez. FWIW, Smith played for 6 more years after leaving Colorado and was a pretty successful hitter in that time.
Among guys worse than Story in this measure, Dickerson and LeMahieu still hit pretty well after leaving the Rockies. A lot of guys further down the list weren't good hitters anywhere.
Not super-encouraging for Story, but I imagine if his road stats were significantly better, he might be looking at a $275+ mil contract like Arenado got.