The image I have is that when her truck came to rest on the median, it was oriented N/S, with the doors oriented E/W. It wouldn't matter which she door she exited, she would still be on the median, relatively safe to either E/B or W/B traffic. In either case, it would be likely that traffic in either direction would be slowed, depending on the location of the damage car, and the number of people who slowed to get a look at the damaged vehicles.
The article said she was struggling to open the passenger door. This suggests that it was damaged. If so, why not just exit the drivers door?
Your ‘image’ is not what the article said.
“...with the driver’s door facing the eastbound traffic lanes.
The article just said the truck wound up on the median, not how far onto the median. She could have been right on the edge of median, with her door opening right into traffic.
Would you get out right into traffic?
Sure sounds like that’s what she was afraid of. Remember she’s 75.
Most likely because she felt safest exiting via the passenger door. Given that she was injured and shaken she did what made the best sense to her at the time.