I noticed that in the video, it was smooth panning over the airport but as soon as you are in the plane it gets choppy. Does external view also have bad frames.
I noticed a lot of AI planes in the video. Is this a custom airport. Can you turn ALL the airport details down (workers, planes etc) and switch off any co-pilot settings.
That level of choppy performance is usually a symtom of exceeding your GPU memory or swaping out to the disk, so I would check IO in task manager as well.