I think if you are both happy with that arrangement that's fine. I personally think it seems a bit like one parent is acting like the adult and treating the other like a child incapable of managing their own life. If my husband packed my lunch for me, I would feel like it was a bit controlling or like he didn't think I could somehow cope enough as an adult to make my own lunch. I wouldn't like that. I think I'd feel like it was similar to someone ordering for me at a restaurant. I can choose my own food, thanks. But I don't think it's a bad thing necessarily if you are both happy with that - you don't mind doing it and he doesn't feel offended by it. My husband would be freaked out if I started to make his lunches. I think he already thinks it's slightly controlling of me to insist on cooking every night and rarely letting him cook (I am particular about food, like eating healthy, lots of fruit and veg, whereas he takes a much more laidback attitude and would be happy to cook with more packaged food and ready meals, which I don't like).
My mum makes my stepdad's lunch for him every day. He works from home (she's now retired). My stepdad is perfectly healthy and able, drives, a scientist, works in a professional job, very well paid, etc. He is literally like 10 feet away from the kitchen has plenty of time to take a break from work (he usually goes to the gym or for a run midday, so time isn't an issue), but she thinks he couldn't manage to make his own lunch (I truly mean that in the sense that she actually thinks he wouldn't know how to do it) and I think she feels fulfilled knowing she did something productive with her time (retired, no children at home obviously, no grandchildren nearby, etc.). She also prepares all his food in advance if she happens to go away and leaves him at home, like an entire week or two of meals. She comes to stay with us for a week or so at a time about 3 times a year. She spends about 2 days cooking before she goes. Pre-bakes him his jacket potatoes and chops up salads for each day. Goes and gets his favourite takeaways and portions them out into individual serving sizes. I think it's completely weird. But it makes them happy, so more power to them. I don't even make up a shopping list for my husband before I go away on trips. He's left to fend for himself.