It’s not hard to take risk when things are only ideas.
You can radically change models, assumptions, and directions when nothing has been built. But as soon as you’ve put ideas into concrete form, risk gets hard.
The reason it gets hard isn’t because you’re limited by the instantiation of the idea in some physical, inescapable way. It’s because humans form attachments to things they’ve built. Once built, you’re attached, once attached, you begin to defend, once in defensive mode, new ideas are treated like enemies, and that means risk-taking gets shut down.
But if you never build, thinking risky thoughts is useless. The trick is to turn your ideas into something real so quickly and so often that you don’t have time to form stagnating attachment to them.