Exactly this.

For a healthy person it’s normally not quick. Your body will try to deal with it quietly, most food poisoning is dismissed as gas, mild cramps etc.

Food poisoning isn’t a reaction to what you ate, that’s an allergy, it’s a reaction to toxins released by pathogens. Those guys take a while to get down to it.

This is why it’s so hard for the CDC to pinpoint outbreaks. Finding a common source for a last meal isn’t so bad. Tracking down 72hrs worth of food, where it came from for many people is crazy hard. I can’t imagine the complexity to trace shit down to some lettuce field in California.