What about FOSS licenses, anyone can simply ignore what for example GPL says and do as they please with the code without copyright. There is simply no case there to fight if it were to happen.
I'm one of the people that uses the GPL because copyright exists. Without copyright, companies lose the incentive to close their source, because the binaries aren't restrictable anyway so they can't profit off that. It just means they shoot themselves in the foot by not showing the source to others for auditing purposes. It would also mean decompiling binaries would be perfectly legal, and distributing the results of that would be legal too.
I'd rather live in a world where nobody can tell you how to distribute information than one where I can try (and personally wouldn't be able to fight jack in court enforcing it without the FSF's help) to force openness on others for the sake of freedom while international companies profiteer off artificial scarcity.
It's still going to be a fight, but it will be fought outside of the court rooms without support of the law. To me that sounds like a step backwards, because even more than today that's a fight where a resource heavy megacorp will have an upper hand.
I don't like the idea of someone that creates something great without compensation, put it out for free, 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. So it's not an incentive to open source and share personal projects either.
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.
Easy to decompile, is not the same as easy to deobfuscate, understand and create deriviative work from. The entire point of GPL or any license is to tell what's allowed to do, that means you can share source code, and have legal means backing you up.
> How would you profit from the work if you can't "sell" the work?
You are the one who say that you can not sell the work. Of course you can, but it may not be relevant to the question of profits here since we are talking about source code, it may be incorporated in an existing system or service or even in a hardware product just to give some examples.
> in how many other disciplines do you expect compensation for finite effort for infinite time?
It's not infinite, it is restricted to a finite time. You do not get compensation unless you sell a product, selling that product it self takes work and investments. The amount you get paid, and if there are any reoccuring payments depends on the terms you are able to negotiate with who ever it is you sell to. It has nothing to do with copyright.