It's true here aswell
The problem with Idea Generation questions is that they don't work with the Stack Exchange format (Q&A with good answers being upvoted), because there is no way to tell what a good answer is. Or seen another way, the response a idea generation querent wants is not a single, clear answer, but a (infinite) spread of suggestions they can frolic in.
If you want such a spread of responses with little to no vote-biasing etc. traditional forums are really good for that, so it is better for everyone to use that format for those kind of queries. We maintain a curated list here and if you want suggestions from some of the same thinking organs as are kicking around here, you can try our chat (which doesn't have the same topic and question restrictions as main, but we do require you to Be Nice).