Once we have a list of ideas, then whittle the list down with the realist and pessimistic people of the group; until there's one obvious way forward or a couple of least worse ideas.
Generally most people are better at telling you what you can't do,
People like me also need time and space to think deeply about certain topics, and a brainstorming session has neither time nor space, so you're immediately limited in the ideas that are presented.
Just clearly write out the scope and purpose, timebox it, and collect/record the ideas, no judgement, not even attribution. Then the next time, see if anything converges, evaluate what can be done.
100%. We had anyone who wanted to join, and nobody’s ideas were better than others. One of our most beloved features was one that our EA came up with in such a session, because she didn’t have the context to think it was hard to do. A few days later, we found an easier way to do it, but we’d never even have looked if it weren’t for the humility and collaboration in that room that day.