My favorite example of this is orange juice. OJ is kept in long term storage to stretch a seasonal crop into year-round availability. What comes out is brown and flavorless! This brown mush is restored to something a person would drink with the addition of "flavor packs" made by the perfume industry. This has the added benefit of giving brands a consistent and repeatable flavor. Regulatory bodies in their wisdom allow this product to be called "100% juice".
You might say well get rid of that too. I'm not arguing this is the ideal food system. But it has to be said, this goes a lot deeper than the easy ones like frosting and fruit loops.
However, flavoring is a distinct profession. Besides that, very few novel compounds are allowed in food compared to fragrance. If any flavoring is synthetic in origin (which is not the same thing as novel, to be clear) then the product must be labeled as artificially flavored. If they call the product 100% juice and added flavoring is used, then that flavoring in turn has to have been sourced from the fruit.
In other words, they're using extracts from real oranges to reconstitute the flavor lost during pasteurization. They can further adjust which parts of the extract they use (called fractions and isolates) to dial in a particular flavor.
Why are we as a society allowing these paperclip maximizing companies to experiment on hundreds of millions of people for their own profits..