I really question this. Unless your food is very, very frozen (deep in the freezer for days) and dense and has enough water to keep it frozen and cold for like 8+ hours without serious risk of bacteria growth and toxins being produced leaving food in a place like that all day seems like a recipe for disaster. Certainly I wouldn't do it for frozen cut up tofu or meat. I suppose if you work in a way that allows you to come home for lunch that might allow it to work but most Americans don't. (CDC says I believe 4 hours is the maximum frozen food that needs to be cooked should be left in the danger zone above freezing/refrigeration temps but below 160+ degrees F)

Given the ideal way to use an air fryer is to expose the contents to the air to get the full benefits of convection cooking which also thaws them more quickly and lets bacteria proliferate or get in it just seems like a poor candidate for it. And if you're doing something like a side like fries that are probably safe to leave all day you still have to make the main meal and fries take like 5 minutes so I question the utility of saving yourself waiting that little time with such a function.

All in all modes like that, remote start works for things like washing machines or clothes driers or coffee machines or pre-heating a conventional oven given that unlike an air fryer can take 10+ minutes.

I think the more likely explanation is it's just more IOT connected nonsense. People buy it, it sells so it gets made and the manufacturers can off-set the costs by selling data profiles on what time people eat meals by gathering that data as well as types of modes used and how long to for example identify people who have midnight snacks or meals, those who work off hours, etc.