Open-source software is open.
As a programmer, I learn from open-source software as that is the purpose of open-source software.
I do copy-paste the code, indeed, I do it all the time, but of course I modify the code to fit mine.
I also use stack overload, discord, even ChatGPT to solve the problem I have, as well as finding inspiration and even better ways to code (like faster speed, using less resources, less RAM, etc).
The thing I dislike about learning from open-source code is... some code is being written so bad, it takes a lot of time to understand it.
A well written code is like reading a book, a story. Most of my code is being writen well (I think, but I don't know about other people who read my code, lol).
Programming is like LEGO. There's LEGO blocks/bricks, and you use the bricks, put one on another until you create a house, a car, an airplane, a train, etc.
Some people (programmers) do better than others, and everyone is learning from each other and sharing how to do better.
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