So someone could invent a new super clean,efficient energy source or better car ,and then decide "people aren't worthy of it" and prevent its use ,to the detriment of all.
Or write ,and begin to sell,the SUPER-APP that would make people want Amigas again,but decide "the heck with it;I don't WANT people to use Amigas anymore..." and use the government and courts to "protect his rights"
That's complete nonsense. You can as well develop a similar invention and sell it as yours. You just may not use *his* one.
In Germany it's even allowed to re-engineer another ones software, but only to learn how it works. You can then write a similar program, but you are not allowed to use a single line of code from the original software.
So what I want to say is, you can examine the MagicWB style and then draw your own icons in that style. Aminet is full of such icons. You just may not use the original MagicWB.
This has nothing to do with preventing other people from benefiting from a great idea. You just may not copy the original product. You can use the idea and create your own similar product. That's competition. But you may not copy the original product. That would be theft.
As a capitalism-oriented USA citizen you should know the difference.