Processed foods are easier to modify. Hence, given corporate greed, they are addictive and unhealthy.

Foods, full stop, is easy to modify. More generally, a producer can arbitrary control any product composition according to their own goals.

Nothing to do with "processed foods" in general, despite a good portion of the affected foods being under that label. It's simply a matter of malicious companies combined with unknowing, unempowered consumers.

By trying to single out something as massively generic as "processed foods", you're just making it easy for companies to avoid the problem: Using and manipulating official definitions to be removed from it as a "solution", justifying the whole thing in the basis of numerous good things being in the same category, drawing attention to other foods in the same category that are more commonly associated with the term despite theirs being way worse, etc.

If you want to fix the problem, you need to attack the problem. That is not processing - it is addiction and glycemic value. Going for the underlying attributes means you cannot redefine your way out of it, and gives consumers a better chance to learn what to actually avoid.