Cat recipes or is it so hard to make balanced diet for a cat?

This is a rather popular scam from the commercial cat food producers. I'll try to describe it here.
Many people feel that it is not right their cat to eat only commercial cat food. Really, sometimes there are pet food recalls or just kidney problems or etc. We know for us- humans that we need to eat various different food to be healthy. So why is so different for cats? Cat manufacturers says - your cat needs only our food for all of its life - see we have food for kittens, food for adults, food for ill cats and so on. And all of them contain all the daily needs of your cat. But is it really true?

Does the science/cat food manufacturer/vet know - what are exactly the daily needs for a cat? There are many health problems related to food. Every two - three years science found new, necessary ingredient for cat foods. And there are mass pet food recalls.

So I think that feeding a cat with commercial cat food is frightening. Many people like me think this way. And here is the catch. People don't just start feeding their cat anything, they search internet and ask their vets - how is the right way to feed my cat?

The answer is a complex table of vitamins, minerals, etc and of course a list of products that contain them and dosages. And all of it counted for a daily need. I won't argue if this numbers are correct or not, and are they even valid for every cat.
But the fact is there, cat owners need to make complex recipes to achieve the daily cat needs, sometimes so complex, that the cat just doesn't want to look at the end creation. (Somewhat disgusting)

But here is my question. Are you yourself eating the same values for your food every day? Are you taking the daily dosages of anything every day? Why does the cat need the same food in exact numbers day after day? Is it really ok?

What is a cat food recipe? Nothing, just a scam. Cats need variety of foods just like people. The only difference is that they need mostly variety of meets with very few supplements?

And here is the simple solution, if you calculate the values of food ingredients for a month it will be a lot more easily to make a healthy diet for a cat. And the cat won't need to eat a strange mixture. For example - my cats love roasted chicken without anything else on it. Why do I need to add anything to a just cooked chicken?

Maybe I am wrong. I am not a vet. This is just my opinion. I'll be happy to see a discussion.