You don't have to directly say you are owed anything, it's how you present yourself through your attitude. Your attitude makes you look entitled and snobby.
You are phrasing this as if having a tight leash on one's own code is somehow a monopoly. Which from my perspective also comes off entitled. Just because you want access to something, but such access is inaccessible, doesn't make it a monopoly. You don't have to like closed source concepts, but don't warp reality based on those biases. Besides, you act as if we can't clean room reverse engineer stuff. Yes that process takes a lot longer, but the point is, it is an option with a legal backbone to work with.
Yes, in person, in a courtroom(s), rather than behind a screen.
We've been tackling these issues for decades, there's more than enough awareness and even legal cases to boot. "Democracy" as a term is just as abused as "freedom" when people want to justify every action and thing said, even the wrong ones. Fighting back is one's right, I believe in that right, but there absolutely is a right way and a wrong way to fight back. "Civil disobedience" consists of rebellious behavior, but even rebellion isn't always in the right.
I prefer to go straight for the jugular, a.k.a. the law. Challenging and making the system squirm seems to be more effective than sitting and being a rebellious individual, residing on the sidelines.
It's illegal because we aren't supposed to have access to that material, it's closed source material under copyright law. Whether any of us likes it or not, it's not our code, it's the company's, they are entitled to it, not us. It's immoral because you know you shouldn't have that material, but you go out of your way to obtain it anyway, and you worsen it for yourself when your motive is spite, rather than reason.
What you are describing aligns with something called
copyleft, hence the existence of things like GPL. Copyright is intended to act as a form of protection for an original expression of an idea. But it's a lot more complicated than this, since there's also things like fair use to consider, especially when closed source concepts are brought to the table. Which, using closed source materials leaked from a company isn't considered fair use. Had you clean room reverse engineered the compiled binary however, then that falls under fair use clauses. Whether or not the flaws of copyright are abused by the company is a separate point. Copying code is theft considering that's technically plagiarism, but also because you don't own any rights to that code. Copyleft's goal post is explicitly for the concept of sharing and reusing code for different projects, so the license justifies such purposes. The same can't be said for leaked copyrighted source code.
Great, however, there's a fine line about leaking and actual fair use. "Research" is explicit depending on the circumstances and varies. You can't sit behind "oh this leak is for research" purposes to try and skirt the system every time stuff like this happens. That's literally a bad faith form of justification in disguise. Spite certainly isn't research either.
What's the point in all of this? I actually care about the moral and integrity of the hobby. Corporations already tend to act like abusive blights when it comes to code and general works. We aren't supposed to stoop to their level. We are supposed to be the difference. I want things to be better, but gambling the hobby, let alone those that branch out, by justifying the leaking and usage of copyrighted, closed source, material isn't how you get around. The last thing I want is something like homebrew to potentially be considered illegal one day, and examples like this being one of many reasons why homebrew is looked down upon. At the end of the day, copyright has gnarly flaws, but there's other ways to address the issues, that doesn't consist of playing Russian roulette with the hobby.