Why do people think Dr. Abigail Tyler from The Fourth Kind is real?

That was an excellent observation and great research that you uncovered about the movie. After it came out, I did the same thing. Now, the reason so many people think it's real is because the actors themselves break the 4th wall, which is a big no-no in the film industry, and actually tell the audience that the film they are about to see is actual footage and is indeed all fact. Plus, when any movie has "actual footage" anyone is bound to believe it. And yes, all the stories about missing people is true but that doesn't necessarily mean alien abduction. I do know that there was a significance about the owl that the victims see, but from real reports, the victim doesn't see the owl until after abduction. If you want to see a movie inspired, not based, by true events I would highly recommend you watch Fire in the Sky or a couple of X- Files, which are inspired by real x-files. Hope this helped. It was still a great movie.