When someone shares a new idea, or makes a pitch, or describes a dream, what would happen if you were enthusiastic?
Perhaps positive thinking is contagious.
Perhaps egging on the other person will help them explore the edges.
And perhaps it will help them overcome their fear and share the very best version of what they have in mind.
You can always say ‘no’ later.
In this moment, your confidence and enthusiasm exist to make the idea better. No harm in that. For either of you.