> they can not create derivative work from it.
You can easily decompile it, and without copyright nobody can tell you want you are allowed to do with it.
> only to have the work taken by some large corporation that manages to profit from the work due to large marketing budgets, sales channels and existing customers, while the author remains uncompensated
How would you profit from the work if you can't "sell" the work? At best they could seek funding to create derivatives of the work. But this does point out a major reason copyright is broken now - in how many other disciplines do you expect compensation for finite effort for infinite time? It should be that your finite work is compensated for finite money during a fixed time period (in my examples, the development of the work).
I'd like to think you could extend plagiarism in the absence of copyright to cover all ideas - ie, you can freely modify, reproduce, or redistribute a work, as long as you aren't falsely claiming it as your own, and upon inquiry you truthfully say where it came from. That is peripheral to actual interactions with information, it is about how you present yourself in relation to them.