I hate copyright disclaimer on the top of code files.

I also hate lint-exclude comments.

For the same reason. Both have nothing to do with the code. Both are talking to a system that wraps around our code. Either the linter, that is not part of our code, but part of our continuous integration pipeline or the legal system that governs our living together in whatever country we are.

But for the linter comments and code checker comments and so on, I get it. They are functional. And I do not know how to add information to a line of code without writing into the code in a better way.

But... Does anyone know if the Copyright claim is even valid? Is it functional?
Don't get me wrong. I understand that code has copyright, but is writing it in code even a good method for it?
First I copyright it to myself or the company that I am working for. But that's the norm, isn't it? It's not like someone can look through my code and say: "He forgot to write it on top of this file, we can steal this file."
So if it was missing it wouldn't change anything. It's just so that it is harder for people to claim they haven't known is was copyrighted... Was that even a legal defense in the first place? "Your honor, I was unaware that I violated a valid copyright," seem like the words with which you'd lose a trial.

But then you upload it to Github. And you choose a license. And... It contradicts what you've written in the file. That sounds like a good legal defense. I was looking at that statement, not at this statement. And if you change your mind you have to find hundreds of copyright notices to change it.

Not to speak about the legal system. Is the code protected in the USA? China? Netherlands? Germany? Different legal systems... Maybe different rules...

I know little about law, but I cannot imagine that copyright notices at the top of code files have any real legal power. And it is strangely enough not a topic I find a lot about.

I start believing it's just like when you draw a nice looking vase and somehow scribble van Gogh on it.