a service that can deliver fresh or at least reasonably high quality food, which is customizable to individual preferences
I'm envisioning a facility tied to an Amazon warehouse or something similar that might be preparing food for >10000 people every day
I really don't see these two things being reconcilable. I eat at eateries very regularly and I become a "regular customer" and people know my name and become familiar with the tweaks I am going to make to my order. Over time, preferences of mine get learned by regular staff.
I don't think AI is anywhere near that point. There are a thousand small things going on that you would have to think to program into the AI and probably wouldn't without deploying and iterating.
So, um, yeah, it sounds like your idea of quality food and mine are not at all on the same page. I think there are ways to get quality food at a reasonable price (I think this because of the aforementioned not wealthy status and years of eating well anyway), but I have serious trouble imagining that a meal-in-a-box delivery service would be it and I have difficulty imagining your idea would be it either.
But thank you for clarifying.
What there is really a market for is a service that can deliver fresh or at least reasonably high quality food, which is customizable to individual preferences, for a reasonable cost (~$5 or so), on-demand, and in a timely manner.