Really? I wouldn't have missed. There was plenty of time for the car to stop based on the video I saw. It looks like 4 seconds of visibility before the driver had to turn the car. It didn't seem like the car was going that fast. There's no way a normal human being paying attention wouldn't be able to get the car to a full stop in that 4 seconds.
From what I understand, Tesla's FSD only uses vision to drive. But we, as humans, use all of our senses to drive. We use vision, smell, sound, as well reasoning and historical knowledge.
If I saw flashing lights in a fog, I would slow down no matter what. I might have heard some sounds, however faint, from the train moving. I would have reasoned that I should always drive slow in the fog, particularly near an area where there are train tracks. I might have sensed that we are driving in train track territory because I saw some tracks around here in the past or I have come across knowledge about this area before that I remembered. Tesla's FSD uses non of these senses.