Whoa! That's fucking gnarly.
The whole Bay Bridge is hectic, but that's right after the tunnel. It's definitely one of the most stressful parts when you are driving into SF because of the light change and cars entering into traffic from Yerba Buena Island.
Any backstory on how the whole thing went down? From a car I've glanced at the bank on the side when you exit the island. You can see it in the photo of the person hiding behind the barrier:
It never crossed my mind to go in from the top. I'm interested in how Evan and the photographer got to the spot.
My first thought would be parking a car on Yerba Buena Island and walking towards the spot. Then either:
a. Dashing through traffic across the Bay Bridge from the exit/on ramp
b. Scaling down from the top of the tunnel, not sure if possible
c. Hiking under the bridge then climbing up, not sure if possible
The only other thing I can think of is pulling off as much as possible to the left after the tunnel next to the barriers, hopping out, maybe throwing down flares / cones behind your pulled over vehicle to hopefully prevent someone from crashing into you, and just barging it. But that wouldn't explain the person hiding on the other side.
A van / car in the lane or off to the side would make sense as to protecting the photographer if they were in the road (or shooting from drivers seat, shotgun, or roof)
Update: Saw Papke's comment on the gram saying he just stood in traffic