A friend noted that there always seems to be a "guy with a 300 page homebrew RPG who shows up at every FLGS".
The thing is, historically a LOT of RPGs had broken, incomplete, or contradictory rules; forcing everyone to be a bit of a game designer to just get it to work at all.
HOWEVER, that same bad design patterns also became they way the knew how to design their own games in turn.
The hurdles to tabletop RPG design are logistically low; "print to PDF" "publish on the internet", but the conceptual hurdles might be quite high if you have to do a lot of unlearning the anti-patterns of broken game design first.
It's why I spent a lot of the early 2000s telling people they should play a wider variety of RPGS with drastically different fundamental assumptions to play ("GMless", "narration trading", "Player driven reward", "No pre-written plot", etc.)
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