Effort is not a good signal for value. Never has been. Just because someone took 10 more hours to finish a task doesn't mean they did a better job or they care more about the result.
But a lack of effort is a good signal for a lack of value.
Eleven times out of ten, your initial idea is garbage. If you write it up, or let AI do that for you, the result is garbage. But if you go through the effort of structuring the idea and thinking about how to express it and how to phrase the details, you may learn what's wrong with the idea and how to improve it.
Effort is, however, an okay proxy for giving a shit.
You’re right that some folks can share more value in fifteen seconds than others might in fifteen hours (setting aside that the first set of folks might have got to that point by way of fifteen years of practice first). That’s hard to gate on. But keeping out shitposters and spammers by requiring a modicum of effort is at least somewhat effective.
Eleven times out of ten, your initial idea is garbage. If you write it up, or let AI do that for you, the result is garbage. But if you go through the effort of structuring the idea and thinking about how to express it and how to phrase the details, you may learn what's wrong with the idea and how to improve it.