I dont think you should should "bash" carbohydrates that much.
The body need all Three, Fat, Proteins and Carbs.
Carbs are a very good energy Source With the right type, and fast carbs that increase insulin is not that bad always.
Even though insulin increases fat Storage, it also is an anabolic hormone (rebuilding) and increases the bodys way of "digesting" or faster/better use of nutrition. It speeds up the use of other nutrition too
A good example is after training, and some in the breakfast. For those two times the body needs fast nutrition, especially after training of course. But not doughnut type of course
All other times, slow. Basically
Proteins are a poor energy Source, and fat, while a good energy Source, the body does not have it readily available, since it is in "Storage", the body must go through a process to get it. It does not always have the time to do that. (Like you burn fat when walking, and carbs when sprinting)
While carbs are more readily available, if the the body needs them NOW!
I am not saying this is Perfect or more right, but if you are active and such, carbs are good, if you do less and not very active, then you can go very low on carbs. But then you also need less fat.
I like to see it as a house being buildt.
The Protein are the material to build walls and New rooms. Too few will not get stuff done, more than you need is better there.
The Carbohydrates are the workers - To few, slow or ineffective building, to many workers and it gets messy and crowded With most sitting around and getting lazy.
The fat are more like the Tools, lubricants and keep the workers happy and is an reserve Source. -Sort of
Insuline is then an sort of boost to the house building, but you cant boost all the time.
But if planned correctly, boosting Works. (after training or?)
And fatty acids are extremely important, because it Controls and regulate all the hormones in the body, so Liquid omega 2-3 times a day does much, especially to a poor Fish eater, but Fish in Food is still noe enough, in my opinion. That also helps stabilizing for example insulin better. I think it is better to drink much omega 3-6-9 and eat somewhat less fat, good fat in regular diet is not so easy to acomplish, for me atleast.
If you think I am wrong, please say so/discuss, I am not an expert, but think about it, and dont believe blindly/to much of what "Professionals" say, and me for that matter
But People are somewhat different, find some sort of middle road that you like that Works for you anyway.
And carbs are a good energy Source! It is like Race Fuel, you can run more compression and more advance on it