The NaNoWriMo folk were really good at this 10 years ago, but I haven't visited that group in a while.
There's also a really good erotica forum which I won't link in public here, but they have a complex application process. The people who get through are mostly respectful, incredibly intelligent and creative, and have quite a bit of ambition. They motivated me to start learning proper writing techniques like outlining and rhe whole Aristotle stuff.
Also I find that screenwriting groups are very mature. The novelist groups tends to want fame and something else, but screenwriters are more interested in what makes a truly good story.
There's also a really good erotica forum which I won't link in public here, but they have a complex application process. The people who get through are mostly respectful, incredibly intelligent and creative, and have quite a bit of ambition. They motivated me to start learning proper writing techniques like outlining and rhe whole Aristotle stuff.
Also I find that screenwriting groups are very mature. The novelist groups tends to want fame and something else, but screenwriters are more interested in what makes a truly good story.