Not sure what your caree is capable of, but my MIL has now gone beyond being able to help herself from the fridge to a cook chill meal, or assemble one herself - eg, if I had left her a nice chicken pie in a cardboard pack in the fridge, and a cook-chill mashed potato with a plastic cover, she can no longer unpack the pie, cut it up, take off the cover of the mashed potato and spoon it out on to the plate, and then put the whole thing in the microwave to heat up (she 'could' physically, but mentally won't do it - it's all 'too much' for her to think about and perform now, as she has got too usedto (me!) placing a nice meal in front of her as she sits by the telly!).......BUT, she has said that if the meal were 'plated up' and left in the fridge, she could (maybe!) put it in the microwave to heat for a couple of minutes, and take it through herself on a tray to the TV chair.....
So that might be a possibility for your caree to do themselves???? You could plate up several meals like that and leave them in the fridge that might last them a day or two? Certainly an incoming carer could heat them up and serve them.
Anyway, just a thought, and it might well not be appropriate for your caree's situation.
Personally, I would most definitely use a 'delivery service' for a suitable meal, and your caree might like the 'someone else' delivering it.
On the general issue, though of a 'healthy diet', to me, if the caree is elderly, I don't see any reason to 'plague' them with healthy food they don't like! My 89 MIL will NOT eat any non-potato vegetable other than possibly mushrooms in a sauce, and won't eat fruit either. But so what? She's 89, and to me, once you get to that age and don't want to eat vegetables, well, I think you've earned the right by then!
If the caree isn't elderly, then it's a different matter of course. But a lot of elderly people seem to revert to 'nursery food' - lots of comfort food that is easy to eat and tasty and not too heavy. And what's the harm at that age?! Personally, I don't see any. So many elderly people were brought up in an age when vegetables were cooked to mush and consisted of overboiled cabbage and carrots - no wonder they aren't keen on them.