Of course it's incomplete. Any explanation of nutrition that doesn't include mention of at least calories, macronutrients and micronutrients isn't useful for understanding what's actually going on or being able to make an effective nutrition plan.
The only benefits ever listed are shelf life, convenience, better margins for the producers, etc.
Availability is the most important value of nutrition, above all else. I expect your comment was made having more nuance, but that just highlights the importance of a clear definition. Without it we are left to guess at what it is you mean.
If you have options when choosing food, a framework that helps you choose the better option is useful. The history of food production is mostly centered around developing options that provide, as a baseline, the three advantages you casually dismiss.
Then why don't we pickle or ferment things anymore ? Ah right because it's not as profitable.
Listening to you guys it seems like Americans in the 80s were starving and we should praise microwave meals for saving us from extinction.
All three preservation techniques are practiced today as they have been since antiquity. It is not clear to me where food so preserved are likely to fall on the processed / ultra-processed spectrum...