Some people definitely did run but I never felt like I was going to be mowed down. I think the bigger issue would be if you have anxiety in a large crowd. Once we got near Pandora, it was a good chunk of time waiting on the bridge in a mass of what felt like a thousand people. It can also be tricky to keep your party together once they open the bridge.For people who have done RD, when they open the turnstiles are being running like mad to get to FoP or is it an orderly walk? I just saw an Epcot RD video and people were sprinting to get to Frozen, combined with a Calvary of people on motorized scooters and parents rushing with strollers.
I would probably do the late night option before the rope drop option if I were to go again without a fP.