Compensation and credit are completely different things. Credit is not compensation. It's an answer to question "Who did this?".
He didn't do whatever he want. He was experiencing a problem, he traced, researched it, debugged it, fixed it, and submitted a patch to The Kernel.
If that was only something "whatever he wanted", the patch would be shot down. The bug is accepted/confirmed on The Kernel side, his patch is being reviewed and deemed "stylistically unacceptable", the reviewer/maintainer wrote his own version, and by pushing the fix w/o attributing him, he effectively claimed that he did all the work from discovery to patching, incl. everything in between.
The maintainer didn't have to accept the patch per se. He could have just written "This bug is discovered, dissected and fixed by $THE_PERSON. Patch is implemented and committed by me. Thanks a lot, $THE_PERSON!".
This is basic human decency. I have my name on many bug reports, either reporting them, or providing more information leading to solution of the bug. I have a couple of patches here and there, and I experienced something similar from another prominent project people interact with every day, but I said that "mneh, whatever".
The author certainly didn't because the treatment he got is really bad, and good for him publicizing this, because these kind of people needs to be known. Well, there might be miscommunication and the story can be completely different, but starting the discussion from somewhere is healthy.