@zzt @techokami yeah reading this, there are some people in the replies fighting the good fight.
I think my opinion now is that Linux is too large, it is insufficiently modular (building out of tree drivers used to be a lot easier) and lkml has long had a reputation for being unfriendly to newcomers. It's a psychological problem more than a technical one, but that barrier exists because the project is huge and has no architectural direction aimed at making it more maintainable.